Physics Letters A via MedWorm.comMedWorm.com provides a medical RSS filtering service. Thousands RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Physics Letters A' source.Sat, 07 Dec 2019 18:32:32 +0100Anisotropic collapse in three-dimensional dipolar Bose-Einstein condensates
https://medworm.com/749278580/anisotropic-collapse-in-three-dimensional-dipolar-bose-einstein-condensates/
Publication date: Available online 6 December 2019Source: Physics Letters AAuthor(s): Boaz Ilan, Jessica TaylorAbstractWe study the (3+1)-dimensional Gross-Pitaevskii / Nonlinear Schrödinger equation describing a dipolar Bose-Einstein condensate. Bound states are computed using accurate numerical techniques. When the dipolar strength is negative, the total number of atoms vs. frequency relationship for these bound states is multi-valued and possesses a cusp point, which corresponds to a “candlestick” ground state. Direct simulations of this ground state exhibit strongly-anisotropic collapse of its nucleus, with different contraction rates along the dipole axis and perpendicular to it. We propose an anisotropic self-similar theory to explain this dynamics. The physical implications are...Physics Letters AjournalsSat, 07 Dec 2019 16:11:34 +0100749278580Monte Carlo study of the critical and the compensation behaviors of the double perovskite Sr2CrIrO6
https://medworm.com/749278579/monte-carlo-study-of-the-critical-and-the-compensation-behaviors-of-the-double-perovskite-sr2criro6/
Publication date: Available online 6 December 2019Source: Physics Letters AAuthor(s): Othmane Amhoud, Noura Zaim, Ahmed Zaim, Mohamed KerouadAbstractThe phase diagrams and magnetic properties of double perovskite Sr2CrIrO6 have been studied by using Monte Carlo simulation based on the heat bath algorithm. The ground-state diagrams of the compound Sr2CrIrO6 have been calculated for different combinations of system parameters. The diagrams obtained are very rich and they give an idea of all the most stable configurations. The effects of the exchange interactions and the crystal field on the phase diagrams and magnetic properties of the system have been examined. A number of interesting phenomena have been observed such as the compensation temperature, the first and second order phase transit...Physics Letters AjournalsSat, 07 Dec 2019 16:11:34 +0100749278579Spatial structures of islands of electron-hole liquid in semiconductor quantum wells
https://medworm.com/749278578/spatial-structures-of-islands-of-electron-hole-liquid-in-semiconductor-quantum-wells/
Publication date: Available online 6 December 2019Source: Physics Letters AAuthor(s): A.A. Chernyuk, V.I. SugakovAbstractThe formation of the different structures of islands of electron-hole liquid in the quantum well is studied in a statistical model. The interaction between the islands of electron-hole liquid is considered by influencing of neighboring islands through exciton gas around the considered island. Two restricted regions were studied: an infinite strip and a disk. The theory gives the possibility to determine the probability of different states realization and to find the most probable state. The dependence of the radius, mutual positions of the electron-hole liquid islands, the number of the islands in the disk on the pumping, temperature and parameters of the system (the siz...Physics Letters AjournalsSat, 07 Dec 2019 16:11:34 +0100749278578The nonlinear wave in semiconductor quantum plasma for laser beam in a self-consistent plasma channel
https://medworm.com/749278577/the-nonlinear-wave-in-semiconductor-quantum-plasma-for-laser-beam-in-a-self-consistent-plasma-channe/
Publication date: Available online 6 December 2019Source: Physics Letters AAuthor(s): Neelam Rani, Manikant Yadav, Y.K. MathurAbstractIn this paper investigating the current task, our emphasis is on distributed a serious laser beam in a self-made plasma channel. As the intensity of the laser beam increases, the medium displays the neuromuscular electrical conductivity functioning as a result of the mass effectiveness of the effectiveness of the electrons as well as the intensity of the electrons. Based on Wentzel–Kramers–Brillouin and paraxial ray theory, the steady-state solution of an intense, Gaussian electromagnetic beam is studied. The differential equation of the distance with the beam width parameter is derived, including the relativistic effects of self-focusing (SF) and self-c...Physics Letters AjournalsSat, 07 Dec 2019 16:11:34 +0100749278577L-mode to H-mode transition triggered by sawtooth-induced heat flux in EAST
https://medworm.com/749119619/l-mode-to-h-mode-transition-triggered-by-sawtooth-induced-heat-flux-in-east/
Publication date: Available online 5 December 2019Source: Physics Letters AAuthor(s): L.M. Shao, G.S. Xu, N. Yan, R. Chen, L. Chen, Y.M. Duan, W. Gao, J.P. Qian, W. Shen, A. Ti, M. Xu, Q. Yu, L. Zhang, T.F. Zhou, the EAST TeamAbstractH-modes induced by sawtooth events can be often observed in discharges with marginal auxiliary power injection in EAST. Poloidal flow shear at the very plasma edge, increasing ∼25% up to the threshold value, is observed just before the L-H transition by means of a fast reciprocating probe array in EAST. This suddenly risen poloidal flow shear, caused by the increased turbulent driven Reynolds force, is motived by the heat pulse originally released by a sawtooth crash at the plasma core. Associated with the critical poloidal flow shear, the local turbulent de...Physics Letters AjournalsSat, 07 Dec 2019 02:11:28 +0100749119619Local impact of Stone–Wales defect on a single layer GNRFET
https://medworm.com/748802102/local-impact-of-stonewales-defect-on-a-single-layer-gnrfet/
Publication date: Available online 4 December 2019Source: Physics Letters AAuthor(s): Hassan Shamloo, Atefeh Nazari, Rahim Faez, Ali ShahhoseiniAbstractIn this work, a new structure of single layer armchair graphene nanoribbon field effect transistor with the Stone–Wales (SW) defect (SWGNRFET) is studied. The simulations are solved with Poisson–Schrödinger equation self-consistently by using Non-Equilibrium Green Function (NEGF) and in the real space approach. The energy band structure is obtained by approximation tight-binding method. The results show that displacement of a defect in the width of the channel of the new structure is led to 50% increase in ION/IOFF ratio only by rotating of a C–C (Carbon–Carbon) bond with similar behavior. But, a remarkable increase of 300% in ION/...Physics Letters AjournalsThu, 05 Dec 2019 21:35:28 +0100748802102Phase transition of nanoscale Au atom chains on NiAl(110)
https://medworm.com/748484121/phase-transition-of-nanoscale-au-atom-chains-on-nial110/
Publication date: Available online 3 December 2019Source: Physics Letters AAuthor(s): Bei-bei Yi, Rui Pang, Xiaoyan Ren, Haizhong Guo, Yuan Shang, Xiangmei Duan, Jun-Hyung Cho, Shunfang LiAbstractRecently, 1D Au single atom chains (SAC) were artificially constructed on the NiAl(110) surface in experiment, which has stimulated various experimental and theoretical investigations on its potential applications such as in microelectronics and catalysis. Here, we reexamine their relative stabilities and formation mechanism on NiAl(110) using first-principles calculations. We reveal that in the range of N=2∼6, the formation of SAC is energetically more stable than that of 1D Au bi-atom chains (BAC), mainly due to the electronic quantum confinement effects. However, beyond N=6, BAC are found to ...Physics Letters AjournalsWed, 04 Dec 2019 17:08:33 +0100748484121Topological modes in radiofrequency resonator arrays
https://medworm.com/748484120/topological-modes-in-radiofrequency-resonator-arrays/
Publication date: Available online 3 December 2019Source: Physics Letters AAuthor(s): Henning U. Voss, Douglas J. BallonAbstractTopological properties of solid states have sparked considerable recent interest due to their importance in the physics of lattices with a non-trivial basis and their potential in the design of novel materials. Here we describe an experimental and an accompanying numerical toolbox to create and analyze topological states in radiofrequency resonator arrays including non-local coupling. These arrays are very easily constructed, offer a variety of geometric configurations, and their eigenfunctions and eigenvalues are amenable to detailed analysis. They offer well defined analogs to coupled oscillator systems in general in that they are characterized by resonances who...Physics Letters AjournalsWed, 04 Dec 2019 17:08:33 +0100748484120Effective potential for emergent Majorana fermions in superconductor systems
https://medworm.com/748484119/effective-potential-for-emergent-majorana-fermions-in-superconductor-systems/
Publication date: Available online 3 December 2019Source: Physics Letters AAuthor(s): A.W. Teixeira, V.L. Carvalho-Santos, J.M. FonsecaAbstractMajorana fermions cannot be found in nature as a free fundamental particle. Nevertheless, in condensed matter systems, they can emerge as a collective excitation. In this work, using functional integration techniques, we calculated the effective potential for emergent Majorana fermions in the Kitaev chain. In this case, we have shown how the superconductor parameter behaves as a function of temperature. Furthermore, we considered surface-induced superconductivity in a Topological Insulator and calculated the effective potential for emergent Majorana fermions in this system. In the case of an s-wave superconductor, we obtained a gap equation equivale...Physics Letters AjournalsWed, 04 Dec 2019 17:08:33 +0100748484119Couette flows between various bounding substrates
https://medworm.com/748484118/couette-flows-between-various-bounding-substrates/
Publication date: Available online 3 December 2019Source: Physics Letters AAuthor(s): L.V. Mirantsev, A.K. AbramyanAbstractMolecular dynamics simulations of equilibrium structures and Couette flows of polar water molecules and nonpolar argon atoms between bounding carbon substrates disposed at the distance h=1.5 nm from each other have been performed. Two symmetric configurations when both substrates have similar, either graphene - like crystalline or amorphous structures, and one asymmetric configuration consisted of one substrate with graphene - like crystalline structure and another substrate with amorphous structure have been considered. It has been found that, in all configurations under consideration, the Couette flow velocity profiles depend strongly on polarity of fluid particles c...Physics Letters AjournalsWed, 04 Dec 2019 17:08:33 +0100748484118The fractional discrete nonlinear Schrödinger equation
https://medworm.com/748484117/the-fractional-discrete-nonlinear-schrdinger-equation/
Publication date: Available online 3 December 2019Source: Physics Letters AAuthor(s): Mario I. MolinaAbstractWe examine a fractional version of the discrete nonlinear Schrödinger (dnls) equation, where the usual discrete laplacian is replaced by a fractional discrete laplacian. This leads to the replacement of the usual nearest-neighbor interaction to a long-range intersite coupling that decreases asymptotically as a power-law. For the linear case, we compute both, the spectrum of plane waves and the mean square displacement of an initially localized excitation in closed form, in terms of regularized hypergeometric functions, as a function of the fractional exponent. In the nonlinear case, we compute numerically the low-lying nonlinear modes of the system and their stability, as a functio...Physics Letters AjournalsWed, 04 Dec 2019 17:08:33 +0100748484117Non-Abelian gauge potentials driven localization transition in quasiperiodic optical lattices
https://medworm.com/747534834/non-abelian-gauge-potentials-driven-localization-transition-in-quasiperiodic-optical-lattices/
Publication date: Available online 22 November 2019Source: Physics Letters AAuthor(s): En Guo Guan, Hang Yu, Gang WangAbstractDerived from quantum waves immersed in an Abelian gauge potential, the quasiperiodic Aubry-André-Harper (AAH) model is a simple yet powerful Hamiltonian to study the Anderson localization of ultracold atoms. Here, we investigate the localization properties of ultracold atoms in quasiperiodic optical lattices subject to a non-Abelian gauge potential, which are depicted by non-Abelian AAH models. We identify that the non-Abelian AAH models can bear the self-duality. We analyze the localization of such non-Abelian self-dual optical lattices, revealing a rich phase diagram driven by the non-Abelian gauge potential involved: a transition from a pure delocalization phase...Physics Letters AjournalsSun, 01 Dec 2019 02:14:27 +0100747534834Lump-type solutions, rogue wave type solutions and periodic lump-stripe interaction phenomena to a (3 + 1)-dimensional generalized breaking soliton equation
https://medworm.com/747534819/lump-type-solutions-rogue-wave-type-solutions-and-periodic-lump-stripe-interaction-phenomena-to-a-/
Publication date: Available online 29 November 2019Source: Physics Letters AAuthor(s): L.T. Gai, W.X. Ma, M.C. LiAbstractIn this paper, we present a bilinear form for an extended (2+1)-dimensional generalized breaking soliton equation, namely, a (3+1)-dimensional generalized breaking soliton (GBS) equation, through using the Hirota direct method. Abundant lump-type solutions, rogue wave type solutions, breather lump wave solutions and interaction solutions are constructed, based on the Hirota bilinear form. Particularly, we generate a type of new interaction solutions in terms of a new combination of quadratic function, trigonometric function and exponential function, namely, a kind of periodic lump-stripe solitons, which is a sort of mixed type solutions of periodic lump-type solitons and...Physics Letters AjournalsSun, 01 Dec 2019 02:14:27 +0100747534819Deterministic twirling with low resources
https://medworm.com/747216400/deterministic-twirling-with-low-resources/
We present a general algebraic method allowing us to choose a set of - typically very few - unitary operators which, when applied randomly and repeatedly, produce the given twirling operation exponentially quickly. The method is applied to twirling operations for bipartite quantum systems with respect to the unitary group U(d)⊗U(d), an essential ingredient in entanglement distillation protocols. In particular, we provide a complete classification of sets of unitary operators capable of performing twirling on two qubits. Moreover, we construct a generic set containing at most three unitary operators achieving the twirling operation for a general two-qudit system. (Source: Physics Letters A)Physics Letters AjournalsFri, 29 Nov 2019 22:11:30 +0100747216400Room temperature high Giant Magnetoresistance graphene based spin valve and its application for realization of logic gates
https://medworm.com/747216399/room-temperature-high-giant-magnetoresistance-graphene-based-spin-valve-and-its-application-for-real/
In this study we carried out first principle calculations for spin dependent electronic transport in our proposed spintronic device consisting of graphene nanoribbon as scattering region with cobalt electrodes and magnesium oxide as tunneling barrier. The I–V Characteristics are calculated by using Non-Equilibrium Green's Function formalism in combination with Semi-Empirical (SE) Extended Huckel Theory (EHT) using Atomistic Tool Kit software at room temperature. The high value of GMR (Giant Magnetoresistance) is recommended for spintronic devices. The results reveal that the device shows a very high GMR ratio of 5.16×104%. The device also shows very low off state current, therefore negligible off state power consumption. The investigation of spin dependent non equilibrium transport is d...Physics Letters AjournalsFri, 29 Nov 2019 22:11:30 +0100747216399Quantum counterpart of measure synchronization: A study on a pair of Harper systems
https://medworm.com/747216398/quantum-counterpart-of-measure-synchronization-a-study-on-a-pair-of-harper-systems/
Publication date: Available online 28 November 2019Source: Physics Letters AAuthor(s): Saikat Sur, Anupam GhoshAbstractMeasure synchronization is a well-known phenomenon in coupled classical Hamiltonian systems over last two decades. Here, synchronization in a pair of coupled Harper systems is investigated both in classical and quantum contexts. It seems that the concept of measure synchronization is restricted in the classical limit as it involves with the phase space. We show the quantum counterpart of the synchronization in a pair of coupled quantum kicked Harper chains. In the quantum context, the coupling occurs between two spins chains via a time and site dependent potential. We use the average interaction energy between the participating systems as an order parameter in both the con...Physics Letters AjournalsFri, 29 Nov 2019 22:11:30 +0100747216398The Lambert-Kaniadakis Wκ function
https://medworm.com/747216397/the-lambert-kaniadakis-w-function/
Publication date: Available online 28 November 2019Source: Physics Letters AAuthor(s): J.L.E. da Silva, G.B. da Silva, R.V. RamosAbstractIn the present work, we introduce the Lambert-Kaniadakis Wκ function. It is a generalization of the Lambert W function that solves the equation Wκ(z)expκ(Wκ(z))=z, where expκ(z) is the κ-exponential, a generalization of the exponential function proposed by Kaniadakis. Following, the Wκ function is used in the definition of the κ-disentropy. Analytical results and numerical calculations of Wκ are shown, as well some applications of the κ-disentropy are discussed. (Source: Physics Letters A)Physics Letters AjournalsFri, 29 Nov 2019 22:11:30 +0100747216397Multiple bright and dark soliton solutions in three component spinor Bose-Einstein condensates
https://medworm.com/746898798/multiple-bright-and-dark-soliton-solutions-in-three-component-spinor-bose-einstein-condensates/
Publication date: Available online 27 November 2019Source: Physics Letters AAuthor(s): V. Rajadurai, V. Ramesh Kumar, R. RadhaAbstractWe investigate a quasi one dimensional spin-1 Bose-Einstein Condensates (BEC) in the absence of an external confinement governed by a system of three coupled Gross-Pitaevskii (GP) equation. Based on the Lax-pair, we construct one soliton solution employing gauge transformation method. In addition, the multiple bright and dark soliton solutions are obtained by properly choosing amplitude dependent parameter in the Lax-pair. The results of the paper emphasizes the richness in the structure of soliton solutions admitted by the spin components, a phenomenon which has never been brought out to the fore. We have also extended the gauge transformation method to gen...Physics Letters AjournalsThu, 28 Nov 2019 18:11:25 +0100746898798Effect of atomic configuration on band gap behaviour in CH3NH3SnxPb1−xI3 perovskites
https://medworm.com/746898797/effect-of-atomic-configuration-on-band-gap-behaviour-in-ch3nh3snxpb1xi3-perovskites/
Publication date: Available online 27 November 2019Source: Physics Letters AAuthor(s): Li Guan, Xiaofang Xu, Yanan Liang, Shichuang Han, Jianxin Guo, Jianglong Wang, Xu LiAbstractThe atomic structure and electronic properties of Sn/Pb mixed organometal halide perovskites were investigated by using first-principles method. The structure-dependent band gap behaviour of tetragonal and pseudocubic MASnxPb1−xI3 (0⩽x⩽1) was emphasized. The configurations with two or more adjacent Sn octahedra in the same layer inducing less tilting of neighbouring octahedra have the lower formation energy. For tetragonal or pseudocubic MASn0.5Pb0.5I3, the configuration of Sn octahedra layer alternating with Pb octahedra layer leads to elongated octahedra along the stacking direction, which stimulates the r...Physics Letters AjournalsThu, 28 Nov 2019 18:11:25 +0100746898797First-principles study on electronic and optical properties of S, N single-doped and S-N co-doped ZnO
https://medworm.com/746898796/first-principles-study-on-electronic-and-optical-properties-of-s-n-single-doped-and-s-n-co-doped-zn/
Publication date: Available online 27 November 2019Source: Physics Letters AAuthor(s): Wei-wei Liu, Cheng-lin Liu, Xiao-bo Chen, Jian-hua Lu, Hong-xia Chen, Zhong-zheng MiaoAbstractThe electronic and optical properties of undoped, N single-doped, S single-doped, and S-N co-doped ZnO were systematically investigated by first-principles calculations. The lattice parameters of S single-doped and S-N co-doped ZnO clearly increased. After N-doping, a strongly localized impurity energy level of N was formed near the Fermi level at the top of valence band (VB). In S-N co-doped ZnO, the localization of N weakened, and the Fermi level went deeper into the VB, indicating that the acceptor energy level of N formed in S-N co-doped system became shallower due to the effect of 3p state of S. Therefore, ...Physics Letters AjournalsThu, 28 Nov 2019 18:11:25 +0100746898796Insights on electronic structures, elastic features and optical properties of mixed-valence double perovskites Cs2Au2X6 (X=F, Cl, Br, I)
https://medworm.com/746898795/insights-on-electronic-structures-elastic-features-and-optical-properties-of-mixed-valence-double-p/
Publication date: Available online 27 November 2019Source: Physics Letters AAuthor(s): Xue Du, Dafang He, Huayue Mei, Yuhan Zhong, Nanpu ChengAbstractIn this work, we investigate the X-dependent crystal, electronic, elastic and optical properties of mixed-valence double perovskites Cs2Au2X6 (X=F, Cl, Br, I) based on first principles. The effects of all atomic sites, especially the [AuX2]− and [AuX4]− clusters with different valences of Au atoms, in the crystal structures of Cs2Au2X6 on their electronic and optical properties have been clarified. Meanwhile, Cs2Au2X6 double perovskites with direct band gaps have strong absorptions, low loss functions and low reflections, and they promise to be used as photoelectric absorption layers of solar cells. (Source: Physics Letters A)Physics Letters AjournalsThu, 28 Nov 2019 18:11:25 +0100746898795An elementary rigorous proof of bulk-boundary correspondence in the generalized Su-Schrieffer-Heeger model
https://medworm.com/746898794/an-elementary-rigorous-proof-of-bulk-boundary-correspondence-in-the-generalized-su-schrieffer-heeger/
Publication date: Available online 27 November 2019Source: Physics Letters AAuthor(s): Bo-Hung Chen, Dah-Wei ChiouAbstractWe generalize the Su-Schrieffer-Heeger (SSH) model with the inclusion of arbitrary long-range hopping amplitudes, providing a simple framework to investigate arbitrary adiabatic deformations that preserve the chiral symmetry upon the bulk energy bands with any arbitrary winding numbers. Using only elementary techniques of solving linear difference equations and applying Cauchy's integral formula, we obtain a mathematically rigorous and physically transparent proof of the bulk-boundary correspondence for the generalized SSH model. The multiplicity of robust zero-energy edge modes is shown to be identical to the winding number. On the other hand, nonzero-energy edge modes...Physics Letters AjournalsThu, 28 Nov 2019 18:11:25 +0100746898794Preparation and characterization of SiO2 nanowires using a SnO2 catalyst
https://medworm.com/746898793/preparation-and-characterization-of-sio2-nanowires-using-a-sno2-catalyst/
Publication date: Available online 27 November 2019Source: Physics Letters AAuthor(s): Hang Lv, Yan Tao, Xibao Yang, Jinglong Zhao, Shucheng Liu, Shuanglong Chen, Qiushi Wang, Ge Zhu, Xiaodong Lu, Bo Liu, Zhen YaoAbstractSiO2 nanowires have been successfully synthesized on the surface of the silicon substrate via a thermal evaporation method using SnO2 powders as the catalysts. The final synthesized product was systematically studied by X-ray powder diffraction (XRD), Raman spectroscopy (RS), scanning electron microscopy (SEM), and electron energy dispersive X-ray (EDX), UV-Visible absorption and photoluminescence (PL) spectroscopy. The results reveal that in the reaction and growth process, the real catalytic effect is Sn and SnOx, and the growth of SiO2 nanowire is most likely controlled...Physics Letters AjournalsThu, 28 Nov 2019 18:11:25 +0100746898793Friction behavior of monolayer molybdenum diselenide nanosheet under normal electric field
https://medworm.com/746739666/friction-behavior-of-monolayer-molybdenum-diselenide-nanosheet-under-normal-electric-field/
This study reveals a possibility of electronically controlling friction in two-dimensional MoSe2 system, with potential applications in solid lubricant and moving parts for MEMS devices. (Source: Physics Letters A)Physics Letters AjournalsThu, 28 Nov 2019 04:05:39 +0100746739666Bright solitary waves on a torus: Existence, stability and dynamics for the nonlinear Schrödinger model
https://medworm.com/746739665/bright-solitary-waves-on-a-torus-existence-stability-and-dynamics-for-the-nonlinear-schrdinger-m/
Publication date: Available online 26 November 2019Source: Physics Letters AAuthor(s): J. D'Ambroise, P.G. Kevrekidis, P. SchmelcherAbstractMotivated by recent developments in the realm of matter waves, we explore the potential of creating solitary waves on the surface of a torus. This is an intriguing perspective due to the role of curvature in the shape and dynamics of the coherent structures. We find different families of bright solitary waves for attractive nonlinearities including ones localized in both angular directions, as well as waves localized in one direction and homogeneous in the other. The waves localized in both angular directions have also been partitioned into two types: those whose magnitude decays to zero and those who do not. The stability properties of the waves are e...Physics Letters AjournalsThu, 28 Nov 2019 04:05:39 +0100746739665Raman-based measurement of carrier concentration in n-type ZnO thin films under resonant conditions
https://medworm.com/746739664/raman-based-measurement-of-carrier-concentration-in-n-type-zno-thin-films-under-resonant-conditions/
Publication date: Available online 26 November 2019Source: Physics Letters AAuthor(s): Zhuang Mao, Cong Fu, Xinhua Pan, Xiangyang Chen, Haiping He, Wei Wang, Yujia Zeng, Zhizhen YeAbstractFor Raman-based carrier concentration determination in thin film semiconductors, above-band-gap excitation is necessary, as the interference from underlying substrate is eliminated by limited photon penetration depth. With resonant Raman spectroscopy, this study investigates the plasmon-phonon coupled modes in n-type ZnO films to non-destructively probe the carrier concentration. The observed coupled mode slightly redshifts from A1(LO) frequency and fails to show monotonic carrier concentration dependency, which differs from the behavior under non-resonant conditions. The correlation between point defects...Physics Letters AjournalsThu, 28 Nov 2019 04:05:39 +0100746739664Overlaps of deformed and non-deformed harmonic oscillator basis states
https://medworm.com/746422914/overlaps-of-deformed-and-non-deformed-harmonic-oscillator-basis-states/
The objective is to provide analytical results for calculating these overlaps (transformation brackets) between deformed and non-deformed basis states in spherical, cylindrical, and Cartesian coordinates. These overlaps can be used for reducing the complexity of different research problems that employ three-dimensional harmonic oscillator basis states, for example as used in coherent state theory and the nuclear shell-model, especially within the context of ab initio symmetry-adapted no-core shell model. (Source: Physics Letters A)Physics Letters AjournalsTue, 26 Nov 2019 23:08:31 +0100746422914An ultra-thin acoustic metasurface with multiply resonant units
https://medworm.com/745626715/an-ultra-thin-acoustic-metasurface-with-multiply-resonant-units/
Publication date: Available online 22 November 2019Source: Physics Letters AAuthor(s): Haozhen Zou, Pan Li, Pai PengAbstractIn this paper, we propose an ultra-thin acoustic metasurface constructed of multiply resonant units to manipulate reflected wavefront. As a counterpart to the Helmholtz resonator (with monopolar resonance) and membrane-type resonator (with dipolar resonance), the multiply resonator are used in metamaterials to induce strong quadrupolar resonance. Here we use the multiply resonator as a new kind of building blocks to make acoustic metasurfaces. The used multiply resonant unit is composed of solid materials, and the acoustic metasurface can work in a water background. We demonstrate that the proposed acoustic metasurface achieves good performance in anomalous reflection...Physics Letters AjournalsSun, 24 Nov 2019 00:11:31 +0100745626715Double optomechanically induced transparency in a Laguerre-Gaussian rovibrational cavity
https://medworm.com/745626714/double-optomechanically-induced-transparency-in-a-laguerre-gaussian-rovibrational-cavity/
Publication date: Available online 22 November 2019Source: Physics Letters AAuthor(s): Jia-Xin Peng, Zheng Chen, Qi-Zhang Yuan, Xun-Li FengAbstractThe optomechanically induced transparency (OMIT), an optomechanical analogue of electromagnetically induced transparency, is a very interesting interference phenomenon. Recently, the studies on the OMIT have been extended to double-OMIT by integrating more optical or mechanical subsystems such as mechanical oscillators, coupled cavities, and atoms in vibrational cavity. In this paper, we demonstrate the double-OMIT can be observed in Laguerre-Gaussian (L-G) rovibrational cavity which was proposed by Bhattacharya et al. (2008) [40], an analog of the double-OMIT in vibrational cavity. The double-OMIT in this research is naturally resulted from a s...Physics Letters AjournalsSun, 24 Nov 2019 00:11:31 +0100745626714Non-Abelian gauge potential driven localization transition in quasiperiodic optical lattices
https://medworm.com/745626713/non-abelian-gauge-potential-driven-localization-transition-in-quasiperiodic-optical-lattices/
Publication date: Available online 22 November 2019Source: Physics Letters AAuthor(s): En Guo Guan, Hang Yu, Gang WangAbstractDerived from quantum waves immersed in an Abelian gauge, the quasiperiodic Aubry-Andre-Harper (AAH) model is a simple yet powerful Hamiltonian to study the Anderson localization of ultracold atoms. Here, we investigate the localization properties of ultracold atoms in quasiperiodic optical lattices subject to a non-Abelian gauge, which are depicted by non-Abelian AAH models. We identify that the non-Abelian AAH models can bear the self-duality. We analyze the localization of such non-Abelian self-dual optical lattices, revealing a rich phase diagram driven by the non-Abelian gauge involved: a transition from a pure delocalization phase, then to coexistence phases, a...Physics Letters AjournalsSun, 24 Nov 2019 00:11:31 +0100745626713Optical characteristics of dilute gallium phosphide bismide: Promising material for near-infra photonic device applications
https://medworm.com/745307688/optical-characteristics-of-dilute-gallium-phosphide-bismide-promising-material-for-near-infra-photo/
We report the optical and electronic characteristics of GaP1−xBix bismide alloys with dilute composition 0≤x≤0.187 in the cubic zinc blende crystallographic phase calculated using a scalar relativistic Full Potential Linear Augmented Plane Wave method within Density Functional Theory. The equilibrium lattice constants are calculated using the improved generalized gradient approximation of Wu and Cohen in excellent agreement with experimental values. A quasi-linear dependence of the lattice parameters on Bi composition is obtained. Electronic structures such as the band gap, total density of states and partial density of states have been discussed using the recently developed approximate modified Becke–Johnson of Tran-Blaha with spin–orbit interaction (SOI) included. Electronic ba...Physics Letters AjournalsFri, 22 Nov 2019 19:41:27 +0100745307688Exploring the effect of dopant (Si, P, S, Ge, Se, and Sb) in arsenene: A DFT study
https://medworm.com/745307687/exploring-the-effect-of-dopant-si-p-s-ge-se-and-sb-in-arsenene-a-dft-study/
Publication date: Available online 21 November 2019Source: Physics Letters AAuthor(s): Qingxiao Zhou, Yanling Liu, Weiwei Ju, Qian Zhang, Jiahui LiAbstractThe structural, electronic and magnetic properties of arsenene were investigated using DFT (density functional theory). The charge transfer, large biding energies, and short bond lengths indicate that the doped structures are robust. Si, S, Ge and Se doping induce magnetic state in arsenene. The principal contribution to the magnetic moment is originates in the p-orbital of dopants and adjacent As atoms, as is suggested by the results of the application of PDOS (Projected Density of States). More importantly, the low effective mass of electrons in arsenene doped by Si, P and Sb implies high carrier mobility, which indicates the three typ...Physics Letters AjournalsFri, 22 Nov 2019 19:41:27 +0100745307687Solid-state synthesis and fluorescence properties of micron Bi2MoO6:Eu3+/C3N4 composite phosphors
https://medworm.com/745307686/solid-state-synthesis-and-fluorescence-properties-of-micron-bi2moo6eu3c3n4-composite-phosphors/
Publication date: Available online 21 November 2019Source: Physics Letters AAuthor(s): Xue Jiang, Shuangju Song, Jiahui Guo, Wenqing Lv, Yunshuai Li, Xiaoqing Guo, Xue Wang, Haiyan Liu, Yuanyuan Han, Liyong WangAbstractThe red emitting composite phosphors Bi2MoO6:Eu3+/C3N4 were prepared via a solid-state method and characterized by different techniques like XRD, SEM, FT-IR, Raman, UV-vis DRS and PL. The effects of reaction temperature and C3N4 amount on the structure and optical properties of Bi2MoO6 were studied in detail. The powder X-ray diffraction patterns showed that the crystal phase structure changed with the increase of temperature. Also, the introduction of C3N4 had a significant impact on photoluminescence properties, which provides a universal strategy for phosphors to improve ...Physics Letters AjournalsFri, 22 Nov 2019 19:41:27 +0100745307686Tunable electronic and optical properties of SnC/BAs heterostructure by external electric field and vertical strain
https://medworm.com/745307685/tunable-electronic-and-optical-properties-of-sncbas-heterostructure-by-external-electric-field-and-/
Publication date: Available online 21 November 2019Source: Physics Letters AAuthor(s): R.Q. Sheng, X.Q. Deng, Z.H. Zhang, Z.Q. FanAbstractBased on the first-principles method, we investigate the electronic structure of SnC/BAs van der Waals (vdW) heterostructure and find that it has an intrinsic type-II band alignment with a direct band gap of 0.22 eV, which favors the separation of photogenerated electron–hole pairs. The band gap can be effectively modulated by applying vertical strain and external electric field, displaying a large alteration of band gap via the strain and experiencing an indirect-to-direct band gap transition. Moreover, the band gap of the heterostructure varies almost linearly with external electric field, and the semiconductor-to-metal transition can be realized in ...Physics Letters AjournalsFri, 22 Nov 2019 19:41:27 +0100745307685Editors
https://medworm.com/745307669/editors/
Publication date: 31 January 2020Source: Physics Letters A, Volume 384, Issue 3Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 22 Nov 2019 19:41:27 +0100745307669Experimental and numerical study of the propagation of focused wave groups in the nearshore zone
https://medworm.com/744992804/experimental-and-numerical-study-of-the-propagation-of-focused-wave-groups-in-the-nearshore-zone/
Publication date: Available online 20 November 2019Source: Physics Letters AAuthor(s): Iskander Abroug, Nizar Abcha, Denys Dutykh, Armelle Jarno, François MarinAbstractThe propagation of focused wave groups in intermediate water depth and the shoaling zone is experimentally and numerically considered in this paper. The experiments are carried out in a two-dimensional wave flume and wave trains derived from Pierson-Moskowitz and JONSWAP spectrum are generated. The peak frequency does not change during the wave train propagation for Pierson-Moskowitz waves; however, a downshift of this peak is observed for JONSWAP waves. An energy partitioning is performed in order to track the spatial evolution of energy. Four energy regions are defined for each spectrum type. A nonlinear energy transfer b...Physics Letters AjournalsThu, 21 Nov 2019 15:11:35 +0100744992804Stochastic resonance in Hopfield neural networks for transmitting binary signals
https://medworm.com/744992803/stochastic-resonance-in-hopfield-neural-networks-for-transmitting-binary-signals/
Publication date: Available online 20 November 2019Source: Physics Letters AAuthor(s): Lingling Duan, Fabing Duan, François Chapeau-Blondeau, Derek AbbottAbstractWe investigate the stochastic resonance phenomenon in a discrete Hopfield neural network for transmitting binary amplitude modulated signals, wherein the binary information is represented by two stored patterns. Based on the potential energy function and the input binary signal amplitude, the observed stochastic resonance phenomena involve two general noise-improvement mechanisms. A suitable amount of added noise assists or accelerates the switch of the network state vectors to follow input binary signals more correctly, yielding a lower probability of error. Moreover, at a given added noise level, the probability of error can be...Physics Letters AjournalsThu, 21 Nov 2019 15:11:35 +0100744992803Estimation of the lowest limit of 1/f noise in semiconductor materials
https://medworm.com/744992802/estimation-of-the-lowest-limit-of-1f-noise-in-semiconductor-materials/
Publication date: Available online 20 November 2019Source: Physics Letters AAuthor(s): Ferdinand GrüneisAbstractA lowest limit of 1/f noise in semiconductor materials has not yet been reported; we do not even know if such a lowest limit exists. 1/f noise in semiconductors has recently been brought into relation with 1/f noise in quantum dots and other materials. These materials exhibit on-off states which are power-law distributed over a wide range of timescales. We transfer such findings to semiconductors, assuming that the g-r process is also controlled by such on-off states. As a result, we obtain 1/f noise which can be expressed as Hooge's relation. Based on the intermittent g-r process, we estimate the lowest limit of 1/f noise in semiconductor materials. We show that this limit is i...Physics Letters AjournalsThu, 21 Nov 2019 15:11:35 +0100744992802Entanglement in three coupled harmonic oscillators
https://medworm.com/744839127/entanglement-in-three-coupled-harmonic-oscillators/
Publication date: Available online 19 November 2019Source: Physics Letters AAuthor(s): Abdeldjalil Merdaci, Ahmed JellalAbstractWe develop an approach in solving exactly the problem of three-body oscillators including general quadratic interactions in the coordinates for arbitrary masses and couplings. We introduce a unitary transformation of three independent angles to end up with a diagonalized Hamiltonian. Using the representation theory of the group SU(3), we explicitly determine the solutions of the energy spectrum. Considering the ground state together with reduced density matrix, we derive the corresponding purity function that is giving rise to minimal and maximal entanglement under suitable conditions. The cases of realizing one variable among three is discussed and know results i...Physics Letters AjournalsThu, 21 Nov 2019 00:38:30 +0100744839127Analytical solution for the collapse motion of an empty hyper-spherical bubble in N dimensions
https://medworm.com/744839126/analytical-solution-for-the-collapse-motion-of-an-empty-hyper-spherical-bubble-in-n-dimensions/
Publication date: Available online 19 November 2019Source: Physics Letters AAuthor(s): Yupeng QinAbstractThe Rayleigh-Plesset equation including the surface tension for the collapse motion of an empty hyper-spherical bubble is considered. Firstly, the collapse time is derived. Secondly, a direct approach based on polynomial function is proposed and employed to construct the analytical solution for this case. It is shown that, when the surface tension is zero, the obtained analytical solution is equivalent to the known one but in a different form. In addition, we also discuss the influences of the relevant physical parameters on the collapse motion. (Source: Physics Letters A)Physics Letters AjournalsThu, 21 Nov 2019 00:38:30 +0100744839126Integrable turbulence for a coupled nonlinear Schrödinger system
https://medworm.com/743597925/integrable-turbulence-for-a-coupled-nonlinear-schrdinger-system/
Publication date: Available online 14 November 2019Source: Physics Letters AAuthor(s): Xi-Yang Xie, Sheng-Kun Yang, Chun-Hui Ai, Ling-Cai KongAbstractIn this manuscript, we aim to study turbulence for a coupled nonlinear Schrödinger system, and find the cause of the appearance of rogue waves in such system. The initial conditions are chosen as the constant backgrounds of unit amplitudes with random perturbations. We list some cases of the standard deviations of one component for the initial conditions, to investigate the influences of the initial conditions on the intensity profiles and peak amplitudes of the two chaotic fields. In addition, sets of complex eigenvalues are illustrated with three various standard deviations, from which we observe that Akhmediev breathers may split into sol...Physics Letters AjournalsSat, 16 Nov 2019 06:39:01 +0100743597925Editors
https://medworm.com/743129153/editors/
Publication date: 20 January 2020Source: Physics Letters A, Volume 384, Issue 2Author(s): (Source: Physics Letters A)Physics Letters AjournalsThu, 14 Nov 2019 11:11:33 +0100743129153Lorentzian solitary wave in a generalised nonlinear Schrödinger equation
https://medworm.com/742972834/lorentzian-solitary-wave-in-a-generalised-nonlinear-schrdinger-equation/
Publication date: Available online 12 November 2019Source: Physics Letters AAuthor(s): M.A. Rego-MonteiroAbstractWe obtain a travelling-wave solution of a generalised nonlinear Schrödinger equation with an additional term of the form Γ(ψ(x,t))=λψ(x,t)q, where λ and q are real constants. Moreover, we show that the density of energy of the system for the travelling-wave solution presents a Lorentzian solitary wave behaviour. (Source: Physics Letters A)Physics Letters AjournalsWed, 13 Nov 2019 20:43:20 +0100742972834Inter-relations between additive shape invariant superpotentials
https://medworm.com/742972833/inter-relations-between-additive-shape-invariant-superpotentials/
Publication date: Available online 12 November 2019Source: Physics Letters AAuthor(s): Jeffry V. Mallow, Asim Gangopadhyaya, Jonathan Bougie, Constantin RasinariuAbstractAll known additive shape invariant superpotentials in nonrelativistic quantum mechanics belong to one of two categories: superpotentials that do not explicitly depend on ħ, and their ħ-dependent extensions. The former group themselves into two disjoint classes, depending on whether the corresponding Schrödinger equation can be reduced to a hypergeometric equation (type-I) or a confluent hypergeometric equation (type-II). All the superpotentials within each class are connected via point canonical transformations. Previous work [19] showed that type-I superpotentials produce type-II via limiting procedures. In this paper ...Physics Letters AjournalsWed, 13 Nov 2019 20:43:20 +0100742972833Macroscopic instructions vs microscopic operations in quantum circuits
https://medworm.com/742972832/macroscopic-instructions-vs-microscopic-operations-in-quantum-circuits/
Publication date: Available online 12 November 2019Source: Physics Letters AAuthor(s): A. Veitia, M.P. da Silva, R. Blume-Kohout, S.J. van EnkAbstractIn many experiments on microscopic quantum systems, it is implicitly assumed that when a macroscopic procedure or “instruction” is repeated many times – perhaps in different contexts – each application results in the same microscopic quantum operation. But in practice, the microscopic effect of a single macroscopic instruction can easily depend on its context. If undetected, this can lead to unexpected behavior and unreliable results. Here, we design and analyze several tests to detect context-dependence. They are based on invariants of matrix products, and while they can be as data intensive as quantum process tomography, they do not...Physics Letters AjournalsWed, 13 Nov 2019 20:43:20 +0100742972832An approach for the calculation of local dielectric properties in nanosized systems on the basis of coupled dipoles method
https://medworm.com/742972831/an-approach-for-the-calculation-of-local-dielectric-properties-in-nanosized-systems-on-the-basis-of-/
Publication date: Available online 12 November 2019Source: Physics Letters AAuthor(s): Kirill A. EmelyanenkoAbstractDespite interest in a description of nanoscale systems properties, there is still a lack of methods that can grasp size dependence and variation across the interface of the static dielectric properties. We propose an approach for the calculation of local nanoscopic electric susceptibility and dielectric permittivity tensors in nanosized systems on the basis of the coupled dipoles method. Requiring only the polarizability of individual molecules, this approach allows one to determine the local dielectric properties of arbitrarily shaped nanoparticles as well as (semi)infinite bodies such as bulk material and infinite films, expanding our ability to predict and govern the behav...Physics Letters AjournalsWed, 13 Nov 2019 20:43:20 +0100742972831Unstable cAMP wave patterns during aggregation of Dictyostelium discoideum cells
https://medworm.com/742972830/unstable-camp-wave-patterns-during-aggregation-of-dictyostelium-discoideum-cells/
Publication date: Available online 12 November 2019Source: Physics Letters AAuthor(s): N.R. Zaoro, C.B. Tabi, A.S. Etémé, T.C. KofanéAbstractFlow-driven formation of unstable patterns of cyclic adenosine monophosphate (cAMP) is investigated in the Martiel-Goldbeter (MG) model. This is predicted via a complex Ginzburg-Landau equation, derived from the MG model, under the so-called modulational instability process. Regions of parameters where patterns exist are discussed analytically and verified numerically. Quasi-periodic waves, spiral seeds and chaotic patterns are found to control information driven in a colony of homogeneously distributed Dictyostelium discoideum cells under the change of the extracellular cAMP degradation rate (ke), the production rate of cAMP (σ) and the advection...Physics Letters AjournalsWed, 13 Nov 2019 20:43:20 +0100742972830Interaction stochasticity may hinder cooperation in the spatial public goods game
https://medworm.com/742661614/interaction-stochasticity-may-hinder-cooperation-in-the-spatial-public-goods-game/
Publication date: Available online 7 November 2019Source: Physics Letters AAuthor(s): Shiping Gao, Te Wu, Long WangAbstractWe propose an analytic model to explore the effect of interaction stochasticity on the evolution of cooperation in spatial public goods game. The results show that whether cooperation can dominate in populations crucially depends on the player's probability of opting-out. Stochastic opting-out enhances cooperation as long as the probability of opting-out is less than a threshold depending on the graph's degree. Otherwise the promoting effect of spatial structures on cooperation is hindered even neutralized by stochastic opting-out. Moreover, there exists an intermediate optimal probability with which the advantage of cooperation over defection is maximized in the evolu...Physics Letters AjournalsTue, 12 Nov 2019 16:35:56 +0100742661614Controlling dielectric properties of cBN by an ultrashort double-pulse light
https://medworm.com/742661609/controlling-dielectric-properties-of-cbn-by-an-ultrashort-double-pulse-light/
Publication date: Available online 11 November 2019Source: Physics Letters AAuthor(s): Xiaoshuang Kong, Feng Wang, Xiaoqin Zhang, Zehui Liu, Suna PangAbstractThe optical responses of wide band gap materials can be manipulated by a purposely designed ultrashort double-pulse light, based on the real-time time-dependent density functional theory. Taking the cubic boron nitride (cBN) as a typical example, we calculate the energy transfer from an ultrashort double-pulse light field to dielectric materials. We show that the purposely designed ultrashort double-pulse light and pulse train can reversibly manipulate the dielectric properties of cBN without damage. By tuning the parameters of light pulse, the cBN will change between isotropic, elliptic and hyperbolic for a particular light frequency...Physics Letters AjournalsTue, 12 Nov 2019 16:35:56 +0100742661609Electronic and transport properties of zigzag phosphorene nanoribbons doped with ordered Si atoms
https://medworm.com/742661608/electronic-and-transport-properties-of-zigzag-phosphorene-nanoribbons-doped-with-ordered-si-atoms/
Publication date: Available online 11 November 2019Source: Physics Letters AAuthor(s): N. Liu, J.B. Liu, S.L. Wang, K.L. YaoAbstractUsing density functional theory (DFT) and the nonequilibrium Green's function method, we explored the electronic structures and transport properties of zigzag phosphorene nanoribbons (ZPNRs) with ordered doping of Si atoms. Our results show that both pristine and Si-doped ZPNRs exhibit metallic properties and the conductance of the doped ZPNRs nanoribbons can be modulated effectively by changing doping positions and concentrations. As different doping positions, different transmission currents can be obtained even with the same doping concentration. Moreover, current amplification factors vary with the doping concentrations. In addition, compared with the pris...Physics Letters AjournalsTue, 12 Nov 2019 16:35:56 +0100742661608Spin dependent electronic transport properties of zigzag black phosphorene nanojunctions induced by H, Li, O, Co asymmetric edge saturations
https://medworm.com/742661607/spin-dependent-electronic-transport-properties-of-zigzag-black-phosphorene-nanojunctions-induced-by-/
Publication date: Available online 11 November 2019Source: Physics Letters AAuthor(s): Aihemaitijiang Sidike, Guanghua Guo, Xiaobo Li, Dongde Li, Yaozhuang Nie, Biaobing Cao, Haiming Duan, Mengqiu LongAbstractTwo-dimensional (2D) material of few-layer black phosphorus (BP) has recently attracted extensive interest owing to its tunable band gap and high carrier mobility. We investigate the electronic transport properties of zigzag black phosphorene nanoribbons (ZBPNRs) with asymmetric H, Li, O and Co edge saturations by employing the density functional theory in combination with the non-equilibrium Green's function. The computational results forecast that different types of saturated atoms at both edge of ribbons mainly contribute to the electronic transport properties of molecular junction...Physics Letters AjournalsTue, 12 Nov 2019 16:35:56 +0100742661607The ground state and the tunnelling dynamics of the Bose-Einstein condensate in a tilted shallow trap
https://medworm.com/742661606/the-ground-state-and-the-tunnelling-dynamics-of-the-bose-einstein-condensate-in-a-tilted-shallow-tra/
Publication date: Available online 11 November 2019Source: Physics Letters AAuthor(s): Yue Jian, Xin Qiao, Yan-Chao Zhang, Ai-Xia Zhang, Ju-Kui XueAbstractThe ground state and the tunnelling dynamics of the Bose-Einstein condensate (BEC) loaded in a tilted shallow trap is studied analytically and numerically. The stable bound state, the quasi-bound state and the diffusion state are predicted. The thresholds for transition between the different states are obtained and the stability diagram in parameter space is presented. The tunnelling dynamics of the system in different states is revealed. The shape of the potential well and the atomic interaction play important role and have coupled effect on the tunnelling dynamics of the system. Furthermore, the resonant tunnelling phenomenon in the pa...Physics Letters AjournalsTue, 12 Nov 2019 16:35:56 +0100742661606Amantadine antiparkinsonian drug adsorption on the AlN and BN nanoclusters: A computational study
https://medworm.com/742661605/amantadine-antiparkinsonian-drug-adsorption-on-the-aln-and-bn-nanoclusters-a-computational-study/
Publication date: Available online 11 November 2019Source: Physics Letters AAuthor(s): Xianghong Sun, Xiaona Wan, Guichen Li, Jing Yu, Vahid VahabiAbstractTo find a sensor for Amantadine (AM) antiparkinsonian drug, we studied its interaction with Al12N12 and B12N12 nanoclusters by density functional theory calculations. The AM molecule attaches via its –NH2 group to the Al or B atoms of Al12N12 or B12N12 with Gibbs free energy change about −31.5 or −26.1 kcal/mol. Increasing the AM concentration, the interaction becomes weaker due to steric effects. The AM adsorbs on the Al12N12 and B12N12 with two different mechanisms, including electrostatic and charge transfer, respectively. The AM significantly reduces the Al12N12 work function from 4.50 to 3.66 eV, increasing the electron field ...Physics Letters AjournalsTue, 12 Nov 2019 16:35:56 +0100742661605Different indicators for Markovian and non-Markovian dynamics
https://medworm.com/742661604/different-indicators-for-markovian-and-non-markovian-dynamics/
Publication date: Available online 11 November 2019Source: Physics Letters AAuthor(s): K. El Anouz, A. El Allati, N. MetwallyAbstractThe Markovianity/non-Markovianity of two different systems are discussed by means of the quantum speed limit time and quantum Fisher information. The first system is described by a central mass particle interacts locally with its surrounding particles, while the second and third models consist of a single qubit interacts with a non-detuning Lorentzian cavity and with a thermal reservoir, respectively. For the first model, the large distance between the central particle and the surrounding particles is guaranty for a fixed quantum speed limit, while the driving time plays the central role on the fixed behavior of the quantum speed limit time. Due to the stable...Physics Letters AjournalsTue, 12 Nov 2019 16:35:56 +0100742661604Unfolding pathway and its identifiability in heterogeneous chains of bistable units
https://medworm.com/741884292/unfolding-pathway-and-its-identifiability-in-heterogeneous-chains-of-bistable-units/
Publication date: Available online 9 November 2019Source: Physics Letters AAuthor(s): Manon Benedito, Stefano GiordanoAbstractWe investigate the behavior of a chain of bistable units with an heterogeneous distribution of energy jumps between the folded and unfolded states. For homogeneous chains, loaded by soft or hard devices, all units at each switching occurrence have the same probability to unfold and it is therefore impossible to identify an unfolding pathway. Conversely, the heterogeneity represents a quenched disorder from the statistical mechanics point of view, and is able to break the symmetry eventually generating an unfolding pathway. We prove that the most probable pathway is realized by arranging the energy jumps in ascending order. Hence, the mechanics of this system is able...Physics Letters AjournalsSat, 09 Nov 2019 17:35:46 +0100741884292The role of spin-orbit coupling on the electronic structure properties of non-centrosymmetric La7Ir3 superconductor
https://medworm.com/741728371/the-role-of-spin-orbit-coupling-on-the-electronic-structure-properties-of-non-centrosymmetric-la7ir3/
Publication date: Available online 7 November 2019Source: Physics Letters AAuthor(s): M. Sahakyan, V.H. TranAbstractWe have carried out the first-principles calculations of the electronic band structure properties of weakly electron correlated, non-centrosymmetric La7Ir3 superconductor (Tc = 2.25 K). We have utilized the GGA-PBE exchange-correlation functionals, implemented in the FP-LAPW ELK code to determine Electronic bands, Densities of States, Fermi surfaces and Electron localization functions. A comparative analysis of scalar relativistic and fully relativistic results reveals the presence of both asymmetric spin - orbit coupling (ASOC) and ordinary spin-orbit coupling (SOC). We have shown that the ASOC with an energy of ΔEASOC≈ 10-60 meV, corresponding to relatively low ratio ΔE...Physics Letters AjournalsSat, 09 Nov 2019 03:39:04 +0100741728371Interaction stochasticity may hinder cooperation in spatial public goods game
https://medworm.com/741728370/interaction-stochasticity-may-hinder-cooperation-in-spatial-public-goods-game/
Publication date: Available online 7 November 2019Source: Physics Letters AAuthor(s): Shiping Gao, Te Wu, Long WangAbstractWe propose an analytic model to explore the effect of interaction stochasticity on the evolution of cooperation in spatial public goods game. The results show that whether cooperation can dominate in populations crucially depends on the player's probability of opting-out. Stochastic opting-out enhances cooperation as long as the probability of opting-out is less than a threshold depending on the graph's degree. Otherwise the promoting effect of spatial structures on cooperation is hindered even neutralized by stochastic opting-out. Moreover, there exists an intermediate optimal probability with which the advantage of cooperation over defection is maximized in the evolu...Physics Letters AjournalsSat, 09 Nov 2019 03:39:04 +0100741728370Frequency dependent hyperpolarizability and two photon excitations in hydrogen atom confined under classical plasma environment
https://medworm.com/741728369/frequency-dependent-hyperpolarizability-and-two-photon-excitations-in-hydrogen-atom-confined-under-c/
Publication date: Available online 7 November 2019Source: Physics Letters AAuthor(s): Sukhamoy Bhattacharyya, Prasanta K. Mukherjee, Burkhard FrickeAbstractFrequency dependent dipole hyperpolarizability of hydrogen atom confined under classical plasma is estimated using nonlinear response theory under a monochromatic electromagnetic field. The screened Coulomb potential is used to model the classical plasma. Time-dependent variation perturbation theory with Slater basis is applied for the first time for such an analysis. As an offshoot, two photon excitations are obtained from the poles of frequency dependent hyperpolarizability. We have specifically studied two photon excited states 2s,3s/3d and 4s/4d from the ground 1s state of H atom. The positions and radial density profiles of two pho...Physics Letters AjournalsSat, 09 Nov 2019 03:39:04 +0100741728369Effects of Co content on microstructure and magnetic property of Fe81-xCoxZr7Mo2B9M1(M=Ge/Cu) alloys
https://medworm.com/741728368/effects-of-co-content-on-microstructure-and-magnetic-property-of-fe81-xcoxzr7mo2b9m1mgecu-alloys/
Publication date: Available online 7 November 2019Source: Physics Letters AAuthor(s): Wanqiu Yu, Liping Lu, Zhong HuaAbstractFe80-xCoxZr7Mo2B10M1(x=10, 20, 30, 40; M=Cu/Ge) amorphous alloy ribbons prepared by melt spinning were annealed at crystallization peak temperatures. The crystallization peak temperature decreases with increasing Co content. The primary crystallization phase of all alloys is only α-Fe(Co) phase. The effects of Co content on grain size (D) and coercivity (Hc) of Cu-containing alloy and on those of Ge-containing alloys are different, i.e., with increasing Co content, both D and Hc of Cu-containing alloys increase gradually, but for Ge-containing alloys, both D and Hc decrease obviously and are still larger than those of Cu-containing alloys. Co content has few effects...Physics Letters AjournalsSat, 09 Nov 2019 03:39:04 +0100741728368In situ-monitored enhancement and quenching effect of Cu nanoclusters on Sm3+ photoluminescence in glass
https://medworm.com/741728367/in-situ-monitored-enhancement-and-quenching-effect-of-cu-nanoclusters-on-sm3-photoluminescence-in-g/
Publication date: Available online 7 November 2019Source: Physics Letters AAuthor(s): José A. JiménezAbstractAn assessment of the influence of heat treatment temperature and retention time on the optical properties of a Cu+ and Sm3+ co-doped phosphate glass of interest to photonic applications is reported. Particularly, the enhancement of the orange-red photoluminescence (PL) from Sm3+ ions has been realized in the glass through the development of non-plasmonic Cu clusters. It was exposed during an in situ isothermal treatment wherein optical absorption and PL were monitored together in real time. Following the PL increase, a drop in the Sm3+ emission intensity was produced concurring with the appearance of Cu nanoparticles (NPs) exhibiting the surface plasmon resonance. Hence, the conne...Physics Letters AjournalsSat, 09 Nov 2019 03:39:04 +0100741728367Phonon focusing effect on thermal conductivity of hexagonal group III-nitrides and silicon carbide crystals
https://medworm.com/741728366/phonon-focusing-effect-on-thermal-conductivity-of-hexagonal-group-iii-nitrides-and-silicon-carbide-c/
Publication date: Available online 7 November 2019Source: Physics Letters AAuthor(s): D.A. Chernodoubov, A.V. InyushkinAbstractThermal conductivity κ of 4H-, 6H-SiC and wurtzite GaN, InN, AlN crystals is calculated accounting phonon focusing effect at low temperatures with only diffusive phonon boundary scattering. The orientation dependence of thermal conductivity is similar in these materials. Thermal conductivity is enhanced in the direction of approximately 45∘ to the c axis up to 27% for GaN, 24% for 6H-SiC, 32% for InN, and 9% for AlN compared to the isotropic case for the circular cross-section and finite-length samples. Contributions of transverse T1 and T2 modes are nearly the same, about 40–45%, while the focusing of T2 mode contributes essentially to the angular dependence ...Physics Letters AjournalsSat, 09 Nov 2019 03:39:04 +0100741728366Strong Jahn-Teller effect at NiO4 tetrahedron in NiCo2O4 spinel
https://medworm.com/741416947/strong-jahn-teller-effect-at-nio4-tetrahedron-in-nico2o4-spinel/
Publication date: Available online 6 November 2019Source: Physics Letters AAuthor(s): Dixing Ni, Shude Liu, Musheng Wu, Xueling Lei, Bo Xu, Seong-Chan Jun, Chuying OuyangAbstractThe local structural distortion and electronic structure of the NiCo2O4 spinel are studied from first-principles calculations. It is found that very strong Jahn-Teller (J-T) distortion occurs to the NiO4 tetrahedron and a large energy gain is obtained, leading to a substantial elongation of the lattice and a cubic to tetragonal phase transition. Further analysis shows that the Ni-3d states are split by not only the broken Td symmetry of the NiO4, chemical bonding interactions also exist between half-occupied dyz and dxz orbitals, which further lower the energy levels of the occupied dyz and dxz states in the spin-u...Physics Letters AjournalsThu, 07 Nov 2019 23:11:52 +0100741416947Interfacial magnetic coupling and the confinement effect of spin electrons for τ-MnAl/Ni multilayers
https://medworm.com/741107181/interfacial-magnetic-coupling-and-the-confinement-effect-of-spin-electrons-for-mnalni-multilayer/
Publication date: Available online 6 November 2019Source: Physics Letters AAuthor(s): Xianmin Zhang, Junwei Tong, Linrui Li, Liuxia Ruan, Fubo Tian, Gaowu QinAbstractThe interface energy and magnetic coupling of τ-MnAl/Ni were studied by first-principles calculations. It was found that τ-MnAl/Ni with Al terminal would be more steady. The magnetic coupling between τ-MnAl film and Ni films oscillated with increasing the thickness of Ni layer. Moreover, the couplings of τ-MnAl/Ni were ferromagnetic and antiferromagnetic when the number of Ni layers were even and odd, respectively. Based on the Fermi surface and energy band analysis, the observed oscillation was attributed to the quantum well states that formed by the confinement of the spin up and spin down band with Δ1 symmetry at Γ‾...Physics Letters AjournalsWed, 06 Nov 2019 18:03:06 +0100741107181Effects of hydroxyl groups and hydrogen passivation on the structure, electrical and optical properties of silicon carbide nanowires
https://medworm.com/740952313/effects-of-hydroxyl-groups-and-hydrogen-passivation-on-the-structure-electrical-and-optical-propert/
Publication date: Available online 4 November 2019Source: Physics Letters AAuthor(s): Ya-Hui Jia, Pei Gong, Shu-Long Li, Wan-Duo Ma, Xiao-Yong Fang, Ying-Ying Yang, Mao-Sheng CaoAbstractThe effects of hydrogen and hydroxyl passivation on the structure, electrical and optical properties of SiCNWs were investigated. The passivation performance of different atoms (groups) were discussed by analyzing the distribution of electronic states and the polarity of chemical bonds. The results show that passivation can improve the stability of SiCNWs structure, and the effect of hydroxyl is better than hydrogen passivation. And hydrogen and hydroxyl passivation both increase the band gap of SiCNWs, and the changing trend of band gap is relevant to the polarity of the covalent bond formed by the passiva...Physics Letters AjournalsWed, 06 Nov 2019 03:12:24 +0100740952313Editors
https://medworm.com/740952297/editors/
Publication date: 9 January 2020Source: Physics Letters A, Volume 384, Issue 1Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 06 Nov 2019 03:12:24 +0100740952297Dissipative optical solitons in asymmetric Rosen-Morse potential
https://medworm.com/739867752/dissipative-optical-solitons-in-asymmetric-rosen-morse-potential/
In this study, stability of solution is examined by numerical analysis to show that solitons are stable for some parameter ranges for both self-focusing and self-defocusing nonlinear modes. Dynamical properties such as evolution and transverse energy flow for both modes are also analyzed. Obtained results are useful for experimental designs and applications in related fields. (Source: Physics Letters A)Physics Letters AjournalsFri, 01 Nov 2019 22:05:47 +0100739867752Symmetry-breaking vortex-lattice of a binary superfluid in a rotating bucket
https://medworm.com/739867751/symmetry-breaking-vortex-lattice-of-a-binary-superfluid-in-a-rotating-bucket/
Publication date: Available online 31 October 2019Source: Physics Letters AAuthor(s): S.K. AdhikariAbstractWe study spontaneous-symmetry-broken phase-separated vortex lattice in a weakly interacting uniform rapidly rotating binary Bose superfluid contained in a quasi-two-dimensional circular or square bucket. For the inter-species repulsion above a critical value, the two superfluid components separate and form a demixed phase with practically no overlap in the vortex lattices of the two components, which will permit an efficient experimental observation of such vortices and study their properties. In case of a circular bucket with equal intra-species energies of the two components, the two components separate into two non-overlapping semicircular domains for all frequencies of rotation Ω...Physics Letters AjournalsFri, 01 Nov 2019 22:05:47 +0100739867751Hamiltonian nature of monopole dynamics
https://medworm.com/739867750/hamiltonian-nature-of-monopole-dynamics/
Publication date: Available online 31 October 2019Source: Physics Letters AAuthor(s): J.M. Heninger, P.J. MorrisonAbstractClassical electromagnetism with magnetic monopoles is not a Hamiltonian field theory because the Jacobi identity for the Poisson bracket fails. The Jacobi identity is recovered only if all of the species have the same ratio of electric to magnetic charge or if an electron and a monopole can never collide. Without the Jacobi identity, there are no local canonical coordinates or Lagrangian action principle. To build a quantum field of magnetic monopoles, we either must explain why the positions of electrons and monopoles can never coincide or we must resort to new quantization techniques. (Source: Physics Letters A)Physics Letters AjournalsFri, 01 Nov 2019 22:05:47 +0100739867750Earthquake forecast based on its nucleation stages and the ensuing electromagnetic radiations
https://medworm.com/739867749/earthquake-forecast-based-on-its-nucleation-stages-and-the-ensuing-electromagnetic-radiations/
Publication date: Available online 31 October 2019Source: Physics Letters AAuthor(s): V. Frid, A. Rabinovitch, D. BahatAbstractA schematic spatial model of an earthquake nucleation is analyzed, and the three stages of the process are identified. Accordingly, the electromagnetic radiations emitted by the fracturing phenomena accompanying each stage are analyzed and it is demonstrated, that the changes of parameters in the persistent specific shape of these radiations during the stages are significant. Specifically, we analyze radiation changes in frequency, directionality and amplitude together with their relations to the fractures' properties across the nucleation process. These results allow us to present a possible method of forecasting, several hours before earthquakes of large magnitud...Physics Letters AjournalsFri, 01 Nov 2019 22:05:47 +0100739867749A three-dimensional frequency selective structure based on the modes coupling of spoof surface plasmon and waveguide transmission
https://medworm.com/739867748/a-three-dimensional-frequency-selective-structure-based-on-the-modes-coupling-of-spoof-surface-plasm/
Publication date: Available online 31 October 2019Source: Physics Letters AAuthor(s): Wei Jiang, Ya Fan, Hua Ma, Jiafu Wang, Leilei Yan, Peng Han, Shaobo QuAbstractA three-dimensional frequency selective structure (3D FSS) was proposed by applying the spoof surface plasmon (SSP) structures into periodic waveguides, which realizes an enhanced broadband transmission in low frequencies, below the cut-off frequency of periodic waveguides. The transmission characteristics of SSP structures and periodic waveguides as well as their coupling modes are investigated by simulation and experiment method. According to our analysis, the pass-band of this 3D FSS can be customized through changing the values of structure parameters and it also has a good angular stability. In addition, this paper also pro...Physics Letters AjournalsFri, 01 Nov 2019 22:05:47 +0100739867748Theory of aerodynamic heating from molecular collision analysis
https://medworm.com/739557036/theory-of-aerodynamic-heating-from-molecular-collision-analysis/
Publication date: Available online 30 October 2019Source: Physics Letters AAuthor(s): Yi Tao, Zhongwu Li, Quan Han, Chengdong Sun, Yan Zhang, Yunfei ChenAbstractAn aerodynamic heating model is derived from molecular collision analysis, in which the rising temperature of a hypersonic flying object as a function of the flying speed in a classical dense monoatomic gas environment is set up. The model predicts that the rising temperature of the hypersonic flying object is independent of the gas density but depends linearly on the gas atomic mass. A nonequilibrium molecular dynamics simulation is carried out to verify the theoretical model. Also, through analyzing the vibrational density of states in the flying objects, it is found that the excited phonon frequency is near the collision frequen...Physics Letters AjournalsThu, 31 Oct 2019 16:39:13 +0100739557036A novel excitation scheme to enhance image resolution in dynamic atomic force microscopy
https://medworm.com/739557035/a-novel-excitation-scheme-to-enhance-image-resolution-in-dynamic-atomic-force-microscopy/
Publication date: Available online 30 October 2019Source: Physics Letters AAuthor(s): Mohammad Safikhani Mahmoudi, Arash BahramiAbstractWe propose a novel multifrequency excitation technique for the non-contact atomic force microscopy (AFM). The probe is excited at two frequencies that are far from resonances while their subtraction is close to the fundamental frequency. Due to combination resonance occurring in nonlinear systems, the response includes a term with frequency equal to subtraction of excitation frequencies. We suggest to employ this term as the main signal for imaging. It is found that the present excitation improves signal sensitivity to sample topography and increases resolution. This technique is especially convenient for highly-damped environments where non-contact AFMs a...Physics Letters AjournalsThu, 31 Oct 2019 16:39:13 +0100739557035Physical properties of ZnSe thin films: Air and vacuum annealing evolution to buffer layer applications
https://medworm.com/739557034/physical-properties-of-znse-thin-films-air-and-vacuum-annealing-evolution-to-buffer-layer-applicati/
Publication date: Available online 30 October 2019Source: Physics Letters AAuthor(s): Ritika Sharma, Himanshu, S.L. Patel, S. Chander, M.D. Kannan, M.S. DhakaAbstractIn order to develop high efficiency solar cell device by replacing conventional hazardous CdS window layer by environmental friendly Zn-based buffer layer, ZnSe thin films of thickness 100 nm were grown on glass and ITO substrates employing electron beam evaporation technique followed by air and vacuum annealing at temperature 100 °C, 200 °C and 300 °C. As-grown and annealed films were subjected to characterization tools like XRD, UV-Vis spectrophotometer, SEM, EDS and source meter. Structural results reveal to the amorphous phase, SEM images indicate uniform deposition without pin holes and EDS patterns conf...Physics Letters AjournalsThu, 31 Oct 2019 16:39:13 +0100739557034Interaction of phonons with discrete breathers in one-dimensional chain with tunable type of anharmonicity
https://medworm.com/739557033/interaction-of-phonons-with-discrete-breathers-in-one-dimensional-chain-with-tunable-type-of-anharmo/
Publication date: Available online 30 October 2019Source: Physics Letters AAuthor(s): F. Hadipour, D. Saadatmand, M. Ashhadi, A. Moradi Marjaneh, I. Evazzade, A. Askari, S.V. DmitrievAbstractIn this paper, we consider the interaction of small amplitude waves (phonons) with standing discrete breather (DB) in the one-dimensional chain of harmonically coupled particles interacting with the anharmonic one-site potential, which can be of hard-type or soft-type anharmonicity. The coefficients of phonon reflection and transmission are calculated numerically. It is found that for the case of hard-type anharmonicity (soft-type anharmonicity) DBs are more transparent for short-wavelength (long-wavelength) phonon waves, while they efficiently reflect short-wavelength (long-wavelength) phonons. In the...Physics Letters AjournalsThu, 31 Oct 2019 16:39:13 +0100739557033First-principles effective Hamiltonian calculations of the electrocaloric effect in ferroelectric BaxSr1−xTiO3
https://medworm.com/739091607/first-principles-effective-hamiltonian-calculations-of-the-electrocaloric-effect-in-ferroelectric-ba/
Publication date: Available online 28 October 2019Source: Physics Letters AAuthor(s): M. Tarnaoui, M. Zaim, M. Kerouad, A. ZaimAbstractFerroelectric materials possess largest thermal response upon variations of the applied electric field, however, the magnitude corresponding to electrocaloric effect (ECE) is relatively too small for cooling applications. Theoretical insight is therefore required to provide additional information, leading to better understanding of the electrocaloric effect with enhanced performance. In this work, electrocaloric effect in BaxSr1−xTiO3 (BST) ferroelectric ceramics is calculated from first-principles based effective Hamiltonian. The influence of the electric field and concentration on ferroelectric properties of BaxSr1−xTiO3 are investigated in detail. In...Physics Letters AjournalsTue, 29 Oct 2019 21:14:40 +0100739091607Spin-orbit interactions in semiconductor superlattice
https://medworm.com/739091606/spin-orbit-interactions-in-semiconductor-superlattice/
Publication date: Available online 28 October 2019Source: Physics Letters AAuthor(s): Ya-Fei HaoAbstractThe purpose of this paper is to theoretically investigate the spin-orbit interactions of common semiconductor superlattices. Spin splitting and spin-orbit interaction coefficients are calculated based on interactions between the interface-related-Rashba effect and Dresselhaus effect. Semiconductor superlattice shows a series of specific characteristics in spin splitting as follows. The spin splitting of the superlattice structure is greater than that of a single quantum well, contributing to significant spin polarization, spin filtering, and convenient manipulation of spintronic devices. The spin splitting of some superlattice structures does not change with variation of the size of some...Physics Letters AjournalsTue, 29 Oct 2019 21:14:40 +0100739091606Second harmonic Hamiltonian: Algebraic and Schrödinger approaches
https://medworm.com/739091605/second-harmonic-hamiltonian-algebraic-and-schrdinger-approaches/
Publication date: Available online 28 October 2019Source: Physics Letters AAuthor(s): T. Mohamadian, H. Panahi, J. NegroAbstractWe study in detail the behavior of the energy spectrum for the second harmonic generation (SHG) and a family of corresponding quasi-exactly solvable Schrödinger potentials labeled by a real parameter b. The eigenvalues of this system are obtained by the polynomial deformation of the Lie algebra sl(2,R) representation space. We have found the bi-confluent Heun equation (BHE) corresponding to this system in a differential realization approach, by making use of the symmetries. By means of a b-transformation from this second-order equation to a Schrödinger one, we have found a family of quasi-exactly solvable potentials. For each invariant n-dimensional subspace of ...Physics Letters AjournalsTue, 29 Oct 2019 21:14:40 +0100739091605One-loop effective potential for two-dimensional competing scalar order parameters
https://medworm.com/739091604/one-loop-effective-potential-for-two-dimensional-competing-scalar-order-parameters/
Publication date: Available online 28 October 2019Source: Physics Letters AAuthor(s): Nei Lopes, Mucio A. Continentino, Daniel G. BarciAbstractUsing the method of the effective potential of quantum field theory, we compute the quantum corrections to the phase diagram of systems with competing order parameters. This is specially useful to study metallic systems with competing antiferromagnetic and superconducting ground states. We focus on the two-dimensional case that is relevant for high Tc superconductors and heavy fermion systems. We consider two different types of couplings between the order parameters and obtain the modifications in the phase diagrams due to critical quantum fluctuations in these systems with conflicting orders. We consider z=1, as well as, a dissipative z=2 dynamics,...Physics Letters AjournalsTue, 29 Oct 2019 21:14:40 +0100739091604Non-Hermitian anomalous skin effect
https://medworm.com/739091603/non-hermitian-anomalous-skin-effect/
Publication date: Available online 28 October 2019Source: Physics Letters AAuthor(s): C. YuceAbstractA non-Hermitian topological insulator is fundamentally different from conventional topological insulators. The non-Hermitian skin effect arises in a nonreciprocal tight binding lattice with open edges. In this case, not only topological states but also bulk states are localized around the edges of the nonreciprocal system. We discuss that controllable switching from topological edge states into topological extended states in a chiral symmetric non-Hermitian system is possible. We show that the skin depth decreases with non-reciprocity for bulk states but increases with it for topological zero energy states. (Source: Physics Letters A)Physics Letters AjournalsTue, 29 Oct 2019 21:14:40 +0100739091603Approximation of quantum assemblages
https://medworm.com/738315748/approximation-of-quantum-assemblages/
Publication date: Available online 25 October 2019Source: Physics Letters AAuthor(s): Xiaojing Yan, Zhi Yin, Longsuo LiAbstractIn this paper, we derive a set of projectors on a large Hilbert space which can universally work for approximating quantum assemblages with binary inputs and outputs. The dimension of the Hilbert space depends on the accuracy of the approximation. (Source: Physics Letters A)Physics Letters AjournalsSat, 26 Oct 2019 22:02:54 +0100738315748Dynamics of emotional contagion in dense pedestrian crowds
https://medworm.com/738315747/dynamics-of-emotional-contagion-in-dense-pedestrian-crowds/
Publication date: Available online 25 October 2019Source: Physics Letters AAuthor(s): Tengfei Xu, Dongdong Shi, Juan Chen, Tao Li, Peng Lin, Jian MaAbstractIn places with high-density pedestrian movements, irrational emotions can quickly spread out under emergency, which may eventually lead to asphyxiation and crushing. It was noticed that a pedestrian's emotion in crowd would change as a result of the influence from other pedestrians. Thus, to explore the dynamics of emotion contagion process in flowing dense pedestrians, two types of pedestrian emotions, i.e., negative and positive have been identified. Taking into account the emotional transit of a pedestrian, a crowd movement model is established in the present paper. We simulate pedestrian movement in a region with periodic boundary c...Physics Letters AjournalsSat, 26 Oct 2019 22:02:54 +0100738315747Temporal and spatial resolutions of optical time stretch imaging with dispersive grating pair
https://medworm.com/738006188/temporal-and-spatial-resolutions-of-optical-time-stretch-imaging-with-dispersive-grating-pair/
Publication date: Available online 24 October 2019Source: Physics Letters AAuthor(s): Lei Yang, Qian Zhu, Chao Wang, Hui Chen, Jincheng Li, Hongbo XieAbstractOptical time stretch imaging (OTSI), providing the capability of capturing the dynamics of fast single-shot or random events, overcomes the fundamental trade-off between imaging speed and sensitivity in ultrafast imaging regions. Lying at the heart of the OTSI is dispersive Fourier transformation, being capable of using large chromatic dispersion to map the spectrum of a broadband ultrashort optical pulse into a stretched time-domain waveform. Dispersive grating pair (DGP) is a unique solution to generate large chromatic dispersion for dispersive Fourier transformation at the wavebands, in which dispersion compensation fibers commonly...Physics Letters AjournalsFri, 25 Oct 2019 17:09:20 +0100738006188Performance improvement of unidimensional continuous-variable quantum key distribution using heralded hybrid linear amplifier
https://medworm.com/738006187/performance-improvement-of-unidimensional-continuous-variable-quantum-key-distribution-using-heralde/
Publication date: Available online 24 October 2019Source: Physics Letters AAuthor(s): Kunlin Zhou, Zhiya Chen, Ying Guo, Qin LiaoAbstractWe propose an improved scheme for unidimensional continuous-variable quantum key distribution (UCVQKD) using heralded hybrid linear amplifier, aiming to simplify the implementation and improve secret key rate. Different from the symmetrical continuous-variable quantum key distribution protocol (CVQKD), this scheme modulates one quadrature of the coherent state with security insurance. The heralded hybrid linear amplifier concatenates a deterministic linear amplifier (DLA) and a noiseless linear amplifier (NLA), which can tune between the high-gain or high noise-reduction for performance enhancement. Security analysis shows that the proposed scheme can be ...Physics Letters AjournalsFri, 25 Oct 2019 17:09:20 +0100738006187Nonlinear integrable systems containing the canonical subsystems of distinct physical origins
https://medworm.com/738006186/nonlinear-integrable-systems-containing-the-canonical-subsystems-of-distinct-physical-origins/
Publication date: Available online 24 October 2019Source: Physics Letters AAuthor(s): Oleksiy O. VakhnenkoAbstractFour new semi-discrete nonlinear integrable systems relevant for physical applications are suggested. Each system contains two coupled subsystems of distinct physical origin. These integrable hybridizations are (1) the Toda-like subsystem coupled with the induced-trapping subsystem of PT-symmetric excitations, (2) the subsystem of Frenkel-like excitons coupled with the subsystem of nontrivial vibrations, (3) two coupled self-trapping subsystems, (4) the Toda-like subsystem coupled with the self-trapping subsystem akin to the charged particle with electromagnetic field. Each hybrid system admits the clear Hamiltonian representation characterized by two pairs of canonical field v...Physics Letters AjournalsFri, 25 Oct 2019 17:09:20 +0100738006186Editors
https://medworm.com/738006169/editors/
Publication date: 27 December 2019Source: Physics Letters A, Volume 383, Issue 36Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 25 Oct 2019 17:09:20 +0100738006169A novel metallic silicon hexaboride, Cmca-B6Si
https://medworm.com/737851652/a-novel-metallic-silicon-hexaboride-cmca-b6si/
This study gives a fundamental investigation on the structural, phonon, and electronic properties of Cmca-B6Si. (Source: Physics Letters A)Physics Letters AjournalsFri, 25 Oct 2019 02:14:58 +0100737851652Light emission properties in a double quantum dot molecule immersed in a cavity: Phonon-assisted tunneling
https://medworm.com/737851651/light-emission-properties-in-a-double-quantum-dot-molecule-immersed-in-a-cavity-phonon-assisted-tun/
Publication date: Available online 23 October 2019Source: Physics Letters AAuthor(s): Vladimir Vargas-Calderón, Herbert Vinck-PosadaAbstractTwo main mechanisms dictate the tunneling process in a double quantum dot: overlap of excited wave functions, effectively described as a tunneling rate, and phonon-assisted tunneling. In this paper, we study different regimes of tunneling that arise from the competition between these two mechanisms in a double quantum dot molecule immersed in a unimodal optical cavity. We show how such regimes affect the mean number of excitations in each quantum dot and in the cavity, the spectroscopic resolution and emission peaks of the photoluminescence spectrum, and the second-order coherence function which is an indicator of the quantumness of emitted light from...Physics Letters AjournalsFri, 25 Oct 2019 02:14:58 +0100737851651Strong chaos of fast scrambling yields order: Emergence of decoupled quantum information capsules
https://medworm.com/737851650/strong-chaos-of-fast-scrambling-yields-order-emergence-of-decoupled-quantum-information-capsules/
Publication date: Available online 23 October 2019Source: Physics Letters AAuthor(s): Masahiro Hotta, Koji YamaguchiAbstractThe information loss problem in black hole evaporation is one of fundamental issues. Its resolution requires more profound understanding of information storage mechanism in quantum systems. In this Letter, we argue that when multiple unknown parameters are stored in large entangled qudits, strong chaos generated by fast scrambling in high temperature limit yields an ordered information storage structure with decoupled quantum information capsules (QICs). A rotational isometry emerges in the quantum Fisher information metric. The isometry is expected to be observed in future experiments on cold atoms in a pure entangled state. We provide a QIC speculation of black hole...Physics Letters AjournalsFri, 25 Oct 2019 02:14:58 +0100737851650Investigation on thermal conductivity of graphene/Si heterostructure with different defect ratios and sizes
https://medworm.com/737851649/investigation-on-thermal-conductivity-of-graphenesi-heterostructure-with-different-defect-ratios-an/
Publication date: Available online 23 October 2019Source: Physics Letters AAuthor(s): Dongjing LiuAbstractThe thermal conductivity (TC) of graphene/Si heterostructures with different defect ratios and sizes was investigated using the molecular dynamics method. As the defect ratio of heterostructure increased, the TC decreased first sharply and then slowly under a high temperature stage. The TC of heterostructure also showed a significant size effect. This phenomenon was explained by phonon dispersion and flip competition. The phonon density of states for the graphene heterostructure with different defect ratios and sizes was obtained to understand the thermal transport mechanism. Analysis showed that with the increase in the defect ratio and when the flexural modes of the heterostructure b...Physics Letters AjournalsFri, 25 Oct 2019 02:14:58 +0100737851649Au-MoOx nanoparticles for LSPR hydrogen detection prepared by a facile anodizing method
https://medworm.com/737851648/au-moox-nanoparticles-for-lspr-hydrogen-detection-prepared-by-a-facile-anodizing-method/
Publication date: Available online 23 October 2019Source: Physics Letters AAuthor(s): M.A. Hosseini, M. Ranjbar, M. SajadiAbstractNowadays, the plasmonic properties of defective transition metal oxides, have attracted great attention in the sensing and catalyst applications. The aim of this paper is to fabricate plasmonic Au-MoOx nanoparticles (NPs) using a facile anodizing in liquid approach to be used as localized surface plasmon resonance (LSPR) hydrogen sensor. Firstly, dark blue MoOx nanosheets with a strong NIR (700–800 nm) LSPR band were obtained. The Au-MoOx NPs (Au size=5–7 nm) were then obtained by adding a gold cation into the blue MoOx liquid base. Thanks to the catalytic properties of Au NP, this system exhibited LSPR hydrogen sensing ability where the LSPR variations allo...Physics Letters AjournalsFri, 25 Oct 2019 02:14:58 +0100737851648Hall effect measurements using low ac magnetic fields and lock-in technique on field effect transistors with molybdenum disulfide channels
https://medworm.com/737534478/hall-effect-measurements-using-low-ac-magnetic-fields-and-lock-in-technique-on-field-effect-transist/
Publication date: Available online 22 October 2019Source: Physics Letters AAuthor(s): Yoshihiro Shimazu, Tatsuya Iwabuchi, Kensuke Arai, Inoru ShioyaAbstractHall effect measurements conventionally rely on the use of dc magnetic fields. For electronic devices made of ultrathin semiconducting materials, such as molybdenum disulfide (MoS2), the dc Hall effect measurements have practical difficulties. Here, we report the results of the Hall effect measurements using ac magnetic fields and a lock-in detection of the Hall voltage for field effect transistors with ultrathin MoS2 channels. The ac Hall effect measurements have some advantages over the dc measurements. The carrier concentration and the Hall mobility were estimated as a function of gate voltage from the results of the ac Hall effect ...Physics Letters AjournalsWed, 23 Oct 2019 21:38:56 +0100737534478Discrete symmetries and nonlocal reductions
https://medworm.com/737217806/discrete-symmetries-and-nonlocal-reductions/
Publication date: Available online 21 October 2019Source: Physics Letters AAuthor(s): Metin Gürses, Aslı Pekcan, Kostyantyn ZheltukhinAbstractWe show that nonlocal reductions of systems of integrable nonlinear partial differential equations are the special discrete symmetry transformations. (Source: Physics Letters A)Physics Letters AjournalsTue, 22 Oct 2019 16:38:46 +0100737217806Editors
https://medworm.com/737217790/editors/
Publication date: 16 December 2019Source: Physics Letters A, Volume 383, Issue 35Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 22 Oct 2019 16:38:46 +0100737217790Nonlinear, nondispersive wave equations: Lagrangian and Hamiltonian functions in the Hodograph transformation
https://medworm.com/736255118/nonlinear-nondispersive-wave-equations-lagrangian-and-hamiltonian-functions-in-the-hodograph-trans/
Publication date: Available online 16 October 2019Source: Physics Letters AAuthor(s): Francesco Pegoraro, Sergei V. BulanovAbstractThe hodograph transformation is generally used in order to associate a system of linear partial differential equations to a system of nonlinear (quasilinear) differential equations by interchanging dependent and independent variables. Here we consider the case when the nonlinear differential system can be derived from a Lagrangian density and revisit the hodograph transformation within the formalism of the Lagrangian-Hamiltonian continuous dynamical systems.Restricting to the case of nondissipative, nondispersive one-dimensional waves, we show that the hodograph transformation leads to a linear partial differential equation for an unknown function that plays th...Physics Letters AjournalsSat, 19 Oct 2019 02:11:34 +0100736255118On the scaling theory of antiferromagnetic ordering in frustrated Kondo lattices
https://medworm.com/736255117/on-the-scaling-theory-of-antiferromagnetic-ordering-in-frustrated-kondo-lattices/
Publication date: Available online 16 October 2019Source: Physics Letters AAuthor(s): V.Yu. IrkhinAbstractA scaling theory of the Kondo lattices with frustrated exchange interactions is developed, criterium of antiferromagnetic ordering being investigated. Depending on the bare model parameters, one or two quantum phase transitions into non-magnetic spin-liquid and Kondo Fermi-liquid ground states can occur with increasing the bare coupling constant. Whereas the renormalization of the magnetic moment in the ordered phase can reach orders of magnitude, spin fluctuation frequency and coupling constant are moderately renormalized in the spin-liquid phase. This justifies application of the scaling approach. (Source: Physics Letters A)Physics Letters AjournalsSat, 19 Oct 2019 02:11:34 +0100736255117Epidemic outbreaks on two-dimensional quasiperiodic lattices
https://medworm.com/736255116/epidemic-outbreaks-on-two-dimensional-quasiperiodic-lattices/
We present a novel kinetic Monte Carlo technique to study the susceptible-infected-removed model in order to simulate epidemic outbreaks on two quasiperiodic lattices, namely, Penrose and Ammann-Beenker. Our analysis around criticality is performed by investigating the order parameter, which is defined as the probability of growing a spanning cluster formed by removed sites, evolving from an initial system configuration with a single random chosen infective site. This system is studied by means of the cluster size distribution, obtained by the Newman-Ziff algorithm. Additionally, we obtained the mean cluster size, and a cumulant ratio to estimate the epidemic threshold. In spite of the quasiperiodic order moves the transition point, compared to periodic lattices, this is not able to alter ...Physics Letters AjournalsSat, 19 Oct 2019 02:11:34 +0100736255116Unidimensional continuous-variable quantum key distribution with discrete modulation
https://medworm.com/736255115/unidimensional-continuous-variable-quantum-key-distribution-with-discrete-modulation/
Publication date: Available online 16 October 2019Source: Physics Letters AAuthor(s): Wei Zhao, Ronghua Shi, Yanyan Feng, Duan HuangAbstractIn this paper, we proposed an unidimensional continuous-variable quantum key distribution (CV-QKD) protocol with discrete modulation, which waives the necessity in one of the quadrature modulations and further simplified the implementation of the CV-QKD protocol. On the basis of the Heisenberg uncertainty relation, we analyze the boundary between the unphysical and physical region. Besides, we utilize a novel proof approach to achieve a lower bound valid of transmission distance. This scheme shows an available method to further simplified the implementation of the QKD. (Source: Physics Letters A)Physics Letters AjournalsSat, 19 Oct 2019 02:11:34 +0100736255115A first-principle investigation of NO2 adsorption behavior on Co, Rh, and Ir-embedded graphitic carbon nitride: Looking for highly sensitive gas sensor
https://medworm.com/735611164/a-first-principle-investigation-of-no2-adsorption-behavior-on-co-rh-and-ir-embedded-graphitic-carb/
Publication date: Available online 15 October 2019Source: Physics Letters AAuthor(s): Hadi Basharnavaz, Aziz Habibi-Yangjeh, Seyed Hossein KamaliAbstractFirst-principle calculations were performed to investigate the adsorption behavior of NO2 gas on the pristine graphitic carbon nitride (gCN) and transition metals (TM)-embedded gCN systems (TM = Co, Rh, and Ir elements) in order to explore the sensing capabilities of gCN systems as toxic gas sensor. The results of adsorption energy revealed that NO2 gas was physisorbed on the pristine gCN, whereas this gas was strongly chemisorbed on the TM-embedded gCN. Additionally, it was found that the interaction of NO2 gas with Ir-embedded gCN (−4.47 eV) is much higher than those of the Co and Rh-embedded systems, alluding to its suitability as a h...Physics Letters AjournalsWed, 16 Oct 2019 16:16:13 +0100735611164Spatially separated spin carriers in three-ports graphene nanoribbons
https://medworm.com/735611163/spatially-separated-spin-carriers-in-three-ports-graphene-nanoribbons/
Publication date: Available online 15 October 2019Source: Physics Letters AAuthor(s): Mingjun Li, Bowen Zeng, Jin Xiao, Can Cao, Mengqiu LongAbstractExporting the different spin signals to different ports is of practical importance to graphene-based spintronic devices. In this work, we have designed a three-ports graphene nanoribbon (GNR) device by inserting square-shaped carbon tetragon (CT) into GNR symmetrically, and calculated the magnetic moment distribution and transmission spectrum by using first-principles calculation and quantum transport simulation. Our results show that CT can bring non-equivalent path for two spin transport channels resulting in one spin is easier to transport than the other in each output port. Overall whole model, the spin states would be separated in real sp...Physics Letters AjournalsWed, 16 Oct 2019 16:16:13 +0100735611163Stability of periodic progressive gravity wave solutions of the Whitham equation in the presence of vorticity
https://medworm.com/735611162/stability-of-periodic-progressive-gravity-wave-solutions-of-the-whitham-equation-in-the-presence-of-/
Publication date: Available online 15 October 2019Source: Physics Letters AAuthor(s): C. Kharif, M. Abid, J.D. Carter, H. KalischAbstractThe modulational instability of two-dimensional nonlinear traveling-wave solutions of the Whitham equation in the presence of constant vorticity is considered. It is shown that vorticity has a significant effect on the growth rate of the perturbations and on the range of unstable wavenumbers. Waves with kh greater than a critical value, where k is the wavenumber of the solution and h is the fluid depth, are modulationally unstable. This critical value decreases as the vorticity increases. Additionally, it is found that waves with large enough amplitude are always unstable, regardless of wavelength, fluid depth, and strength of vorticity. Furthermore, thes...Physics Letters AjournalsWed, 16 Oct 2019 16:16:13 +0100735611162Beyond the Vegard's law: solid mixing excess volume and thermodynamic potentials prediction, from end-members
https://medworm.com/735611161/beyond-the-vegards-law-solid-mixing-excess-volume-and-thermodynamic-potentials-prediction-from-en/
Publication date: Available online 15 October 2019Source: Physics Letters AAuthor(s): Marcello Merli, Alessandro PaveseAbstractA method has been developed, herein presented, to model binary solid solutions' volume, enthalpy and Gibbs energy using the energy state functions, E(V,S), of the end-members only. The E(V,S)s are expanded around an unknown mixing volume, VMix, and the fundamental equilibrium equation −(∂E/∂V)S=P is used to determine VMix. VMix allows us to model enthalpy, straightforwardly. The same argument holds using Helmholtz energy, F(V,T), in place of E(V,S), and the equilibrium equation becomes −(∂F/∂V)T=P. One can readily determine the Gibbs free energy, too. The method presented remarkably simplifies computing of solid mixings' thermodynamic properties and mak...Physics Letters AjournalsWed, 16 Oct 2019 16:16:13 +0100735611161Self-consistent mean-field theory to anisotropic ferrimagnetic chain with bond alternation
https://medworm.com/735290857/self-consistent-mean-field-theory-to-anisotropic-ferrimagnetic-chain-with-bond-alternation/
Publication date: Available online 14 October 2019Source: Physics Letters AAuthor(s): Xin Yang, Yuge Chen, Bin ChenAbstractWe investigate the finite temperature properties of anisotropic ferrimagnetic chain with bond alternation. The spin excitation spectrum as well as the thermodynamic quantities are calculated by means of the extended self-consistent mean-field theory. Two branches of energy spectrum are obtained and the energy gap between them is 1.7641 at zero temperature which agrees quite well with other numerical results. The contribution of bonding alternation δ, anisotropy λ and magnetic field H to the energy gap are present in this research. The other thermodynamic quantities varying with δ and λ, such as ground state energy e, free energy f, specific heat cm, magnetization m...Physics Letters AjournalsTue, 15 Oct 2019 11:06:27 +0100735290857A shape memory alloy-based tunable phononic crystal beam attached with concentrated masses
https://medworm.com/735290856/a-shape-memory-alloy-based-tunable-phononic-crystal-beam-attached-with-concentrated-masses/
Publication date: Available online 14 October 2019Source: Physics Letters AAuthor(s): Xu-Feng Lv, Shao-Feng Xu, Zhi-Long Huang, Kuo-Chih ChuangAbstractShape memory alloys (SMAs) in phononic crystals (PCs) or metamaterials mostly serve as smart inserts or local resonators to generate tunable bandgaps for other structures. In this letter, we address the method for creating tunable bandgaps in structures made of SMA. Specifically, we consider concentrated masses, realized by steel balls, as attachments on a SMA. To provide a design guideline, we derived the closed-form bandgap formula of the proposed SMA PC beam. As the bandgap order increases, the coefficient of the nth Bragg bandgap width decreases. In addition, the practical final beam enlarges bandgap edges than ideally infinite PCs or me...Physics Letters AjournalsTue, 15 Oct 2019 11:06:27 +0100735290856High coercivity in α-Fe2O3 nanostructures synthesized by surfactant-free microwave-assisted solvothermal method
https://medworm.com/734650912/high-coercivity-in-fe2o3-nanostructures-synthesized-by-surfactant-free-microwave-assisted-solvoth/
In this report, the cube-like shaped α-Fe2O3 nanostructures were prepared by the simple microwave-assisted solvothermal method without using any surfactants. The as-prepared samples were characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The well dispersed and size-controlled cubic-like shaped α-Fe2O3 nanostructures were obtained by systematic variation of solvents, reaction temperature and time. The magnetic studies manifest that the magnetic properties of α-Fe2O3 samples are strongly dependent on the shape and size of the nanostructures. The maximum coercivity (Hc) ∼5.6 kOe is observed for Fe-160-30 sample, which is originating from the varying synthesis conditions, oriented sub-particle st...Physics Letters AjournalsSun, 13 Oct 2019 01:37:30 +0100734650912Preface
https://medworm.com/734650903/preface/
Publication date: Available online 11 October 2019Source: Physics Letters AAuthor(s): Ming Liu, Ziyao Zhou, Zhongqiang Hu (Source: Physics Letters A)Physics Letters AjournalsSun, 13 Oct 2019 01:37:30 +0100734650903Splitting and rotating of optical vortices due to non-circular symmetry in amplitude and phase distributions of host beams
https://medworm.com/734329847/splitting-and-rotating-of-optical-vortices-due-to-non-circular-symmetry-in-amplitude-and-phase-distr/
Publication date: Available online 10 October 2019Source: Physics Letters AAuthor(s): Guo Liang, Wenjing ChengAbstractDiscussed is the dynamics of optical vortices carrying multi-topological charges, which are nested in optical envelopes with non-circular symmetric amplitudes and phases. As a result of the non-circular symmetry either in amplitudes or in phases, the vortices can split in pairs from the centers of the host beams. During the splitting process of every constituent vortex, its carried integer charges evolves into fractional ones. Furthermore, an overall rotations of the host optical envelopes are found to happen in the splitting process. The theoretical results may find potential applications in beam shaping and engineering. (Source: Physics Letters A)Physics Letters AjournalsFri, 11 Oct 2019 21:12:21 +0100734329847Editors
https://medworm.com/734329830/editors/
Publication date: 5 December 2019Source: Physics Letters A, Volume 383, Issue 34Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 11 Oct 2019 21:12:21 +0100734329830Effects of electric and magnetic fields on electronic states and transport of a Hall bar
https://medworm.com/734009434/effects-of-electric-and-magnetic-fields-on-electronic-states-and-transport-of-a-hall-bar/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): Gen-Hua Liu, Hui-Ying Zhou, Piao-Rong XuAbstractWe study the edge-state band and transport property for a HgTe/CdTe quantum well Hall bar under the combined coupling of a transverse electric field and a perpendicular magnetic field. It is demonstrated that a weak magnetic field can protect one of the two edge states, open or enlarge a gap of the other edge state in the Hall bar. However, an appropriate electric field can remove the gap, restoring the quantum spin Hall effect. Using the scattering matrix method, we study the electronic transport of the system. We find that the electric field can not only make the switch from pure spin-up to spin-down current, but also open or close the edge-state channels i...Physics Letters AjournalsThu, 10 Oct 2019 16:39:27 +0100734009434High thermoelectric performance can be achieved in two-dimensional (PbTe)2 layer
https://medworm.com/734009431/high-thermoelectric-performance-can-be-achieved-in-two-dimensional-pbte2-layer/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): Caiyu Sheng, Dengdong Fan, Huijun LiuAbstractThe electronic, phonon and thermoelectric transport properties of (PbTe)2 layer are investigated by using first-principles pseudopotential method combined with Boltzmann transport equation. We demonstrate that there is a valley degeneracy of six for the top valence band, which leads to larger carrier concentration and thus higher electrical conductivity without obvious reduction in the Seebeck coefficient. Moreover, the intrinsic van der Waals interactions between neighboring Pb layers induce additional phonon scattering and thus ultrasmall lattice thermal conductivity. As a consequence, ZT>2.0 can be realized in a wide temperature region from 650 to 1000 K with...Physics Letters AjournalsThu, 10 Oct 2019 16:39:27 +0100734009431Enhancement of image quality by using metamaterial inspired energy harvester
https://medworm.com/734009426/enhancement-of-image-quality-by-using-metamaterial-inspired-energy-harvester/
Publication date: Available online 9 October 2019Source: Physics Letters AAuthor(s): Fatih Ozkan Alkurt, Olcay Altintas, Meliksah Ozakturk, Muharrem Karaaslan, Oguzhan Akgol, Emin Unal, Cumali SabahAbstractMetamaterial energy harvester based subwavelength imaging structure is presented. Besides, 2×2 array patch antenna is designed to create incident radiated signal towards the proposed harvester structure. Harvested energy is converted to DC voltage signal by using Schottky diodes and each cell is represented by 256 grey levelled pixel value. Therefore, any incident electromagnetic wave placed in the operating frequency range can be monitorized. In the experimental study, experiments are realized with and without antenna to investigate the effects of instantaneous electromagnetic waves an...Physics Letters AjournalsThu, 10 Oct 2019 16:39:27 +0100734009426Emergence of seismic metamaterials: Current state and future perspectives
https://medworm.com/733849887/emergence-of-seismic-metamaterials-current-state-and-future-perspectives/
Publication date: Available online 7 October 2019Source: Physics Letters AAuthor(s): Stéphane Brûlé, Stefan Enoch, Sébastien GuenneauAbstractFollowing the advent of electromagnetic metamaterials, researchers working in wave physics have translated concepts of engineered media to acoustics, elastodynamics and diffusion processes. In elastodynamics, seismic metamaterials have emerged in the last decade for soft soils structured at the meter scale, and have been tested with full-scale experiments on holey soils. Born in the soil, seismic metamaterials have emerged from the field of tuned-resonators buried in the soil, around building's foundations or near the soil-structure interface as local seismic isolators. Forests of trees have been interpreted as above-surface resonators, and coined...Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849887Resonant-interaction-induced Rydberg antiblockade and its applications
https://medworm.com/733849886/resonant-interaction-induced-rydberg-antiblockade-and-its-applications/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): Jin-Lei Wu, Jie Song, Shi-Lei SuAbstractDifferent from the conventional Rydberg antiblockade (RAB) regime that either requires weak Rydberg-Rydberg interaction (RRI), or compensates the RRI-induced energy shift by introducing off-resonant interactions, we show that RAB regime can be achieved by resonantly driving the transitions between ground state and Rydberg state under strong RRI. The Rabi frequencies are of small amplitude and time-dependent harmonic oscillation, which plays a critical role for the presented RAB. The proposed unconventional RAB regime is used to construct high-fidelity controlled-Z (CZ) gate and controlled-not (CNOT) gate in one step. Each atom requires single external driving. And th...Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849886Detection of exhaled gas by γ-graphyne and twin-graphene for early diagnosis of lung cancer: A density functional theory study
https://medworm.com/733849885/detection-of-exhaled-gas-by-graphyne-and-twin-graphene-for-early-diagnosis-of-lung-cancer-a-dens/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): Roya Majidi, Marzieh NadafanAbstractIn lung cancer, primary diagnosis is quite essential to guarantee human health. In this work, the capability of γ-graphyne and twin-graphene sheets to detect typical breath gases such as benzene, styrene, aniline, and o-toluidine is studied based on density functional theory. The results indicate that these gases are physisorbed on γ-graphyne and twin-graphene. Because of relatively low gas binding strength between gases and γ-graphyne and twin-graphene, these sheets can be proper for the practical gas sensors with a fast recovery rate. Both γ-graphyne and twin-graphene have semiconducting properties before and after gas adsorption. Adsorption of the gases decreases ...Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849885High coercivity in α-FeO32 nanostructures synthesized by surfactant-free microwave-assisted solvothermal method
https://medworm.com/733849884/high-coercivity-in-feo32-nanostructures-synthesized-by-surfactant-free-microwave-assisted-solvoth/
In this report, the cube-like shaped α-Fe2O3 nanostructures were prepared by the simple microwave-assisted solvothermal method without using any surfactants. The as-prepared samples were characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The well dispersed and size-controlled cubic-like shaped α-Fe2O3 nanostructures were obtained by systematic variation of solvents, reaction temperature and time. The magnetic studies manifest that the magnetic properties of α-Fe2O3 samples are strongly dependent on the shape and size of the nanostructures. The maximum coercivity (Hc) ∼ 5.6 kOe is observed for Fe-160-30 sample, which is originating from the varying synthesis conditions, oriented sub-particle s...Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849884Gaussian states as minimum uncertainty states
https://medworm.com/733849883/gaussian-states-as-minimum-uncertainty-states/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): Shuangshuang Fu, Shunlong Luo, Yue ZhangAbstractIn bosonic fields, Gaussian states, which consist of a rather wide family of states including coherent states, squeezed states, thermal states, etc., have many classical-like features, and are usually defined from the mathematical perspective in terms of characteristic functions. It is well known that some special Gaussian states, such as coherent states, are minimum uncertainty states for the conventional Heisenberg uncertainty relation involving canonical pair of position and momentum observables. A natural question arises as whether all Gaussian states can be characterized as minimum uncertainty states. In this work, we show that indeed Gaussian states coi...Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849883Characteristics of anodic glow pulsed plasma
https://medworm.com/733849882/characteristics-of-anodic-glow-pulsed-plasma/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): M. Kiruthika, G. ShanmugavelayuthamAbstractUsing the triple Langmuir probe, the characteristics of the glowing plasma adjacent to a constricted anode is obtained. The glow discharge is generated by applying a train of high voltage pulses between the constricted anode and cylindrical cathode with a pulse frequency of 2 kHz at 50% duty cycle. The axial plasma characteristics along the central line of the anode shows crest and trough resembling a double layer. The bulk plasma showed uniform electron density outside the glow. The visual images show an enhancement in the volume of the glow consistent with the discharge current. The mechanism behind the particular double layer characteristics around the anode is...Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849882Mechanical properties, lattice thermal conductivity, infrared and Raman spectrum of the fullerite C24
https://medworm.com/733849881/mechanical-properties-lattice-thermal-conductivity-infrared-and-raman-spectrum-of-the-fullerite-c2/
In this study, the stability, mechanical properties, lattice thermal conductivity, electronic structure, infrared and Raman spectrum of sp3 hybridized low-density fullerite C24 were investigated according to density functional theory (DFT) calculations. It was found that the fullerite C24 was both thermodynamic and dynamic stable. Quasi-harmonic approximation and Grüneisen parameter calculations clarified why the fullerite C24 had a positive thermal expansion coefficient at low temperature. The fullerite C24 also exhibited excellent mechanical properties. Interestingly, the Vickers hardness of carbon allotropes was found to almost be linear proportional to the density of a carbon material. HSE06 electronic structure calculations showed that it was a semiconductor with direct bandgap of 2....Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849881Gravitational wave emission from quadrupole Josephson junction device
https://medworm.com/733849880/gravitational-wave-emission-from-quadrupole-josephson-junction-device/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): Victor AtanasovAbstractWe suggest a hybrid quantum mechanical/classical set up capable of gravitational wave emission. The proposed device consists of two superconducting tunneling junctions which act as quantum voltage-to-frequency converters and produce oscillation of the charges (masses) in the superconducting condensate. The classical interpretation of the set up is associated with the particular arrangement which leads to suppression of the dipole radiation and formation of time dependent quadrupole mass moment - the gravitational wave source. The proposed device converts electrical energy/momentum into gravitational ones thus suggesting a form of propulsion. Provided the reverse effect: curvature-to-...Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849880Nonlocal behaviors of spin correlations in the Haldane-Shastry model
https://medworm.com/733849879/nonlocal-behaviors-of-spin-correlations-in-the-haldane-shastry-model/
Publication date: Available online 8 October 2019Source: Physics Letters AAuthor(s): Maowen Tang, Yan HeAbstractThe nonlocal factors of spin correlations are introduced for lattice spin models. Based on this concept, we investigate the nonlocal behavior of the Haldane-Shastry model with or without ring frustration. The ground state and spin correlations of the Haldane-Shastry model are calculated for both even and odd number of spins, then the nonlocal factors can be deduced analytically. It is found that the nonlocal factor due the ring frustration is the same as the Heisenberg model. (Source: Physics Letters A)Physics Letters AjournalsThu, 10 Oct 2019 02:15:23 +0100733849879Comment on “Convergence towards asymptotic state in 1-D mappings: A scaling investigation” [Phys. Lett. A 379 (2015) (18–19) 1246-1250]
https://medworm.com/732408813/comment-on-convergence-towards-asymptotic-state-in-1-d-mappings-a-scaling-investigation-phys/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): Mauricio Girardi-Schappo, Marcelo H.R. TragtenbergAbstractNonequilibrium phase transitions are characterized by the so-called critical exponents, each of which is related to a different observable. Systems that share the same set of values for these exponents also share the same universality class. Thus, it is important that the exponents are named and treated in a standardized framework. In this comment, we reinterpret the exponents obtained by Teixeira et al. [1] for the logistic and cubic maps in order to correctly state the universality class of their bifurcations, since these maps may describe the mean-field solution of stochastic spreading processes. (Source: Physics Letters A)Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408813Bifurcations and solutions for the generalized nonlinear Schrödinger equation
https://medworm.com/732408812/bifurcations-and-solutions-for-the-generalized-nonlinear-schrdinger-equation/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): Lingxi Du, Yuhuai Sun, Dashan WuAbstractThe theory of bifurcations for dynamical system is employed to construct new exact solutions of the generalized nonlinear Schrödinger equation. Firstly, the generalized nonlinear Schrödinger equation was converted into ordinary differential equation system by using traveling wave transform. Then, the system's Hamiltonian, orbits phases diagrams are found. Finally, six families of solutions are constructed by integrating along difference orbits, which consist of Jacobi elliptic function solutions, hyperbolic function solutions, trigonometric function solutions, solitary wave solutions, breaking wave solutions, and kink wave solutions.Graphical abstract (Source: Phys...Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408812Fisher information for endohedrally confined hydrogen atom
https://medworm.com/732408811/fisher-information-for-endohedrally-confined-hydrogen-atom/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): Liangyong Wu, Shengqi Zhang, Bowen LiAbstractElectron localization and delocalization of endehedrally confined hydrogen atom has been investigated employing Fisher information theory. Confinement has been modeled using a spherical Gaussian-type potential. B-spline bases expansion method was used to solve the Schrödinger equation to obtain the required energy eigenvalues and the corresponding wave functions. Changes in energies with depths of potential are explained using Hellmann-Feynman theorem. The behavior of Fisher information against the confining potential depths and positions are demonstrated. Moreover, our results show that Fisher information is an effective way to measure the localization of vale...Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408811Separation coordinates in Hénon-Heiles systems
https://medworm.com/732408810/separation-coordinates-in-hnon-heiles-systems/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): Nicola SottocornolaAbstractIn this paper we apply the method of the Kowalewski's Conditions to separate the seven Hénon-Heiles integrable systems. For each of them we provide explicitly the separation coordinates in the form of eigenvalues of a matrix M called Control Matrix. A couple of systems (HH3 KK and HH4 1:12:16) are presented and discussed in a more general form than usually in the literature. We show that the process of separation of coordinates can be reduced, at the end, to the choice of a single function and, eventually, a vector field transversal to the Lagrangian foliation in an extended phase space. (Source: Physics Letters A)Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408810Free energy of nonideal two-component thermal plasma
https://medworm.com/732408809/free-energy-of-nonideal-two-component-thermal-plasma/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): A.V. Shavlov, V.A. DzhumandzhiAbstractThe free energy of nonideal two-component thermal plasma is calculated using the Poisson-Boltzmann equation. The possibility of the existence of a metastable state is shown for a component of heavy multicharged particles with particle charge values bounded from below and plasma temperature values bounded from above. The component of oppositely-charged light singly-charged particles and plasma generally do not feature the metastable state. (Source: Physics Letters A)Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408809Numerical and experimental investigations on the band-gap characteristics of metamaterial multi-span beams
https://medworm.com/732408808/numerical-and-experimental-investigations-on-the-band-gap-characteristics-of-metamaterial-multi-span/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): Shuaimin Hao, Zhijing Wu, Fengming Li, Chuanzeng ZhangAbstractA novel metamaterial multi-span beam with periodic simple supports and local resonators is designed and investigated. The frequency responses of the proposed metamaterial multi-span beam are computed by the spectral element method (SEM). The accuracy and feasibility of the SEM are verified by the finite element method (FEM) and the vibration experiments. The results show that the metamaterial multi-span beam could generate both the local resonance band-gaps in the low-frequency ranges and the Bragg band-gaps in the medium and high frequency regions. By adjusting the natural frequencies of the local resonators, the thickness of the base beam and ...Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408808Optical solitons with complex Ginzburg–Landau equation having three nonlinear forms
https://medworm.com/732408807/optical-solitons-with-complex-ginzburglandau-equation-having-three-nonlinear-forms/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): Saima Arshed, Anjan Biswas, Fouad Mallawi, Milivoj R. BelicAbstractThis paper secures, dark, singular and dark–singular combo optical soliton solutions to complex Ginzburg–Landau equation that is considered with three nonlinear forms. Two forms of integration architectures provide these solutions. (Source: Physics Letters A)Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408807Supersonic crowdion clusters in 2D Morse lattice
https://medworm.com/732408806/supersonic-crowdion-clusters-in-2d-morse-lattice/
Publication date: Available online 3 October 2019Source: Physics Letters AAuthor(s): I.A. Shepelev, E.A. Korznikova, D.V. Bachurin, A.S. Semenov, A.P. Chetverikov, S.V. DmitrievAbstractFor the first time, the class of simple N-crowdions is expanded to M×N-crowdions, dynamics of which is investigated in two-dimensional triangular Morse lattice by means of molecular dynamics simulations. The M×N-crowdions are excited by giving initial velocity V0 to the chosen M×N block of atoms along a close-packed direction. In the notations here N is the number of neighboring atoms in one close-packed row and M is the number of neighboring rows. The 2×1, 2×2 and 2×4-crowdions are chosen for consideration. It is found that the 2×1 and 2×2-crowdions demonstrate stable dynamics, while the 2×2-crowdi...Physics Letters AjournalsFri, 04 Oct 2019 19:12:23 +0100732408806Nonlocal heat conduction in suspended graphene
https://medworm.com/732091954/nonlocal-heat-conduction-in-suspended-graphene/
Publication date: Available online 2 October 2019Source: Physics Letters AAuthor(s): Mingtian XuAbstractIn order to investigate the mechanism of the extremely high thermal conductivity of the suspended graphene, a nonlocal heat conduction model of heat conduction in two-dimensional materials under a temperature gradient along the length direction is proposed. This model shows that the heat transport of the suspended graphene along the length direction under the nonlocal effect in the width and thickness directions demonstrates a similarity with the viscous Poiseuille flow between two parallel plates. Based on this model, the dimensional crossover of heat conduction in few-layer graphene is demonstrated and the impact of temperature variation on the thermal conductivity of graphene is inves...Physics Letters AjournalsThu, 03 Oct 2019 14:39:30 +0100732091954Ultra-broadband metamaterial absorber for infrared transparency window of the atmosphere
https://medworm.com/732091953/ultra-broadband-metamaterial-absorber-for-infrared-transparency-window-of-the-atmosphere/
Publication date: Available online 2 October 2019Source: Physics Letters AAuthor(s): Ling Li, Hongjie Chen, Zhengwei Xie, Weidong Chen, Wenpeng Zhang, Wuming Liu, Ling LiAbstractThe broadband absorber at the wavelength range from 8 to 13 μm has attracted much attention because this range is exactly the infrared transparency window of the atmosphere. In this Letter, we propose a new structure of ultra-broadband absorber, which is composed of a periodic array of single-sized titanium (Ti) patches and a sandwich (Ti/SiO2/Ti) plane. In the infrared transparency window of the atmosphere, the structure proposed can achieve nearly perfect absorption with the maximal absorptivity up to 99% for the wavelength range from 9.77 to 10.69 μm, and a high average absorptivity of 96.7% from 8 to 13 μm. ...Physics Letters AjournalsThu, 03 Oct 2019 14:39:30 +0100732091953The effect of probe-Ohmic environment coupling type and probe information flow on quantum probing of the cutoff frequency
https://medworm.com/732091952/the-effect-of-probe-ohmic-environment-coupling-type-and-probe-information-flow-on-quantum-probing-of/
Publication date: Available online 2 October 2019Source: Physics Letters AAuthor(s): Fahimeh Salari Sehdaran, Mohammad H. Zandi, Alireza BahrampourAbstractThis work aims to compare results of dissipating and pure dephasing single-qubit probes in characterizing the cutoff frequency of a harmonic reservoir Ohmic spectral density. In particular, we proved that a dissipating single-qubit improves the estimation precision of the cutoff frequency estimator. The information backflow and outflow of the dissipating and the dephasing single-qubit are compared. The relation between the quantum Fisher information and the information outflow and backflow of the probe is obtained. The results show that difference between the values of information outflow and backflow of a dissipating single-qubit is lar...Physics Letters AjournalsThu, 03 Oct 2019 14:39:30 +0100732091952Convective boson-fermion pairing mode in one-dimensional oscillating optical superlattice
https://medworm.com/731933075/convective-boson-fermion-pairing-mode-in-one-dimensional-oscillating-optical-superlattice/
Publication date: Available online 1 October 2019Source: Physics Letters AAuthor(s): Tieyan SiAbstractA convective pairing mode of a boson-fermion mixture of ultracold atoms confined in an optical superlattice can be induced by the transformation between two optical superlattice configurations. This convective pairing mode only exists in discrete momentum vector zones for pairing energy gaps. The energy spectrum of gapped states is characterized by topological winding numbers, which is characterized by topological winding numbers characterize the energy spectrum of gapped states. Two neighboring gapped states are bridged by an unstable chiral linear mode, which drives the boson-fermion pair into directional motion for a short period but remains static in the supersymmetric phase with time-...Physics Letters AjournalsThu, 03 Oct 2019 00:39:28 +0100731933075Pressure controllable phase transition in MoTe2 by the interlayer band occupancy
https://medworm.com/731933074/pressure-controllable-phase-transition-in-mote2-by-the-interlayer-band-occupancy/
Publication date: Available online 1 October 2019Source: Physics Letters AAuthor(s): J.G. Si, W.J. Lu, H.Y. Lv, B.C. Zhao, Y.P. SunAbstractHigh pressure can effectively control the phase transition of MoTe2 in experiment, but the mechanism is still unclear. In this work, we show by first-principles calculations that the phase transition is suppressed and 1T′ phase becomes more stable under high pressure, which originates from the pressure-induced change of the interlayer band occupancies near the Fermi energy. Specifically, the interlayer states of 1T′ phase tend to be fully occupied under high pressure, while they keep partially occupied for the Td phase. The increase of the band occupancies makes the 1T′ phase more favorable in energy and prevents the structure changing from 1T′ ...Physics Letters AjournalsThu, 03 Oct 2019 00:39:28 +0100731933074Editors
https://medworm.com/731933057/editors/
Publication date: 28 November 2019Source: Physics Letters A, Volume 383, Issue 33Author(s): (Source: Physics Letters A)Physics Letters AjournalsThu, 03 Oct 2019 00:39:28 +0100731933057Asymptotic behavior of two-electron expectation values in two-electron excited states
https://medworm.com/730827510/asymptotic-behavior-of-two-electron-expectation-values-in-two-electron-excited-states/
Publication date: Available online 27 September 2019Source: Physics Letters AAuthor(s): H.E. Montgomery, Jacob Katriel, K.D. SenAbstractSingly-excited states of the two-electron atom cease being bound when Z→1 (from above), the outer orbital becoming infinitely diffuse. The asymptotic relationslimZ→1(Z−1)k〈(1sns)1,3S|r12k|(1sns)1,3S〉=〈(n−1)s(0)|rk|(n−1)s(0)〉, where k=−1,1,2,3,⋯, are demonstrated to hold. Here, (n−1)s(0) is a hydrogenic s orbital with principal quantum number (n−1). New, more nuanced light is shed on the already challenged dogma that the Pauli principle keeps the electrons further apart in the triplet than in the corresponding singlet.Graphical abstract (Source: Physics Letters A)Physics Letters AjournalsSat, 28 Sep 2019 22:12:34 +0100730827510Security of continuous-variable measurement-device-independent quantum key distribution with imperfect state preparation
https://medworm.com/730514316/security-of-continuous-variable-measurement-device-independent-quantum-key-distribution-with-imperfe/
Publication date: Available online 26 September 2019Source: Physics Letters AAuthor(s): Hong-Xin Ma, Peng Huang, Tao Wang, Shi-Yu Wang, Wan-Su Bao, Gui-Hua ZengAbstractThe state preparation operation of continuous-variable measurement-device-independent quantum key distribution (CV-MDI-QKD) protocol may become imperfect in practical applications. We address the security of the CV-MDI-QKD protocol based on imperfect preparation of the coherent state under realistic conditions of lossy and noisy quantum channel. Specifically, we assume that the imperfection of Alice's and Bob's practical state preparations equal to the amplification of ideal modulators and lasers at both Alice's and Bob's sides by untrusted third-parties Fred and Gray employing phase-insensitive amplifiers (PIAs), respective...Physics Letters AjournalsFri, 27 Sep 2019 18:12:27 +0100730514316Editors
https://medworm.com/730514302/editors/
Publication date: 18 November 2019Source: Physics Letters A, Volume 383, Issue 32Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 27 Sep 2019 18:12:27 +0100730514302Encapsulation of glycine inside C60 fullerene: Impact of confinement
https://medworm.com/730199921/encapsulation-of-glycine-inside-c60-fullerene-impact-of-confinement/
Publication date: Available online 25 September 2019Source: Physics Letters AAuthor(s): Mozhgan Shahamirian, S.M. AzamiAbstractConfinement of glycine inside C60 fullerene (gly@C60) is analyzed via geometrical, energetic and deformation density of intermolecular interaction. Results shows that the both fragments are significantly deformed due to the compression imposed by the confinement. Also kinetic energy pressure and relaxation deformation density analyses are used to describe the nature of interaction between components, and topological analysis of the steric deformation density in gly@C60 was carried out to find the critical points of the charge deformation due to steric effects. The relevance between different types of energies and charge displacement show almost identical sensitivit...Physics Letters AjournalsThu, 26 Sep 2019 14:12:37 +0100730199921Effect of the third component on charge transfer character in ternary organic solar cells with a cascade-type electronic structure
https://medworm.com/730042377/effect-of-the-third-component-on-charge-transfer-character-in-ternary-organic-solar-cells-with-a-cas/
Publication date: Available online 24 September 2019Source: Physics Letters AAuthor(s): Lingxia Xu, Chong Li, Xiaotao Hao, Kun GaoAbstractBy incorporating a third component into the host donor/acceptor organic components, we theoretically investigate the effects of its electronic structure and spatial location on charge transfer character. It is found that both of the two factors can modulate the distribution of transferred charges, and thus change the role of the third component in charge transfer (i.e., electron donor or acceptor). The binding energy of the formed charge transfer (CT) state is also determined by the two factors. Especially, we find an optimized spatial location of the third component, at which the binding energy of the formed CT state has a minimum value. It suggests tha...Physics Letters AjournalsThu, 26 Sep 2019 00:09:23 +0100730042377Correlation effects and configuration of a one-dimensional bipolaron
https://medworm.com/730042376/correlation-effects-and-configuration-of-a-one-dimensional-bipolaron/
Publication date: Available online 24 September 2019Source: Physics Letters AAuthor(s): N.I. Kashirina, V.D. LakhnoAbstractThe aim of the work is to study the structure of a one-dimensional (1D) bipolaron, taking into account three types of correlation effects: such as interelectronic correlations caused by the direct dependence of the wave function on the distance between electrons as well as the one-center and two-center correlations. Gaussian orbitals with exponentially-correlated multipliers were used for variational calculations. In is shown that in the domain of existence of an 1D optical bipolaron – unlike in a 3D system – a two-center bipolaron is formed. The one-center bipolaron configuration becomes energetically favorable as compared to the two-center one for VC≤1.2 (where...Physics Letters AjournalsThu, 26 Sep 2019 00:09:23 +0100730042376Enhanced out-of-plane thermoelectric performance of Cmcm SnSe phase by uniaxial strain
https://medworm.com/730042375/enhanced-out-of-plane-thermoelectric-performance-of-cmcm-snse-phase-by-uniaxial-strain/
Publication date: Available online 24 September 2019Source: Physics Letters AAuthor(s): Donglin Guo, Chunhong Li, Qiqi Yang, Kejian Li, Bin Shao, Dengming Chen, Yilong Ma, Jianchun Sun, Xianlong Cao, Wen Zeng, Zhongchang Wang, Haie ZhuAbstractThe electronic structure and thermoelectric property of SnSe are calculated by first-principles methods and Boltzmann transport theory. The deformation potential approximation and single parabolic band model are employed to compute the relaxation time. Owing to the accurate electronic structure calculated by Tran-Blaha modified Becke-Johnson (TB-mBJ) potential, the theoretical data (Seebeck coefficient, electrical conductivity and figure of merit ZT) are in good agreement with experimental data. Results show that the uniaxial strain not only affects t...Physics Letters AjournalsThu, 26 Sep 2019 00:09:23 +0100730042375Modelling the effect of heterogeneous vaccination on metapopulation epidemic dynamics
https://medworm.com/729725828/modelling-the-effect-of-heterogeneous-vaccination-on-metapopulation-epidemic-dynamics/
Publication date: Available online 23 September 2019Source: Physics Letters AAuthor(s): Yongwang Gong, Michael SmallAbstractVaccination as an epidemic control strategy has a significant effect on epidemic spreading. In this paper, we propose a novel epidemic spreading model on metapopulation networks to study the impact of heterogeneous vaccination on epidemic dynamics, where nodes represent geographical areas and links connecting nodes correspond to human mobility between areas. Using a mean-field approach, we derive the theoretical spreading threshold revealing a non-trivial dependence on the heterogeneity of vaccination. Extensive Monte Carlo simulations validate the theoretical threshold and also show the complex temporal epidemic behaviours above the threshold. (Source: Physics Letter...Physics Letters AjournalsTue, 24 Sep 2019 19:12:28 +0100729725828Transmission control by asymmetric electromagnetically induced transparency-like metamaterials in transverse electromagnetic waveguide
https://medworm.com/729725827/transmission-control-by-asymmetric-electromagnetically-induced-transparency-like-metamaterials-in-tr/
Publication date: Available online 23 September 2019Source: Physics Letters AAuthor(s): Fulya Bagci, Baris AkaogluAbstractWe numerically and experimentally present passive and active electromagnetically induced transparency-like metamaterials in a TEM waveguide under normal excitation. Asymmetry of the metamaterial unit cell leads to the splitting of the radiative resonance. Surface current distributions are analyzed to account for each resonance. Moreover, by implementing a varactor diode to one of the gaps of the double-split ring resonator, electromagnetically induced transmission-like band is shifted in frequency and the corresponding bandwidth is modulated. A modulation ratio of 29.5 dB in transmission is experimentally demonstrated by only increasing the bias voltage 4 volts. (Source...Physics Letters AjournalsTue, 24 Sep 2019 19:12:28 +0100729725827Control of light in a quantized four level graphene atomic system via self and cross-Kerr nonlinearity
https://medworm.com/729725826/control-of-light-in-a-quantized-four-level-graphene-atomic-system-via-self-and-cross-kerr-nonlineari/
Publication date: Available online 23 September 2019Source: Physics Letters AAuthor(s): Usman Khan, Bakht Amin, Arif Ullah, Kefayat UllahAbstractWe investigate self and cross-Kerr nonlinearity in a four level quantized graphene atomic medium. The absorption, dispersion, transmission and subluminal/superluminal behaviors of a probe light field are studied. An amplification of the probe light field is observed in the absorption spectrum. The normal and anomalous slope of dispersion is also investigated at the positive/negative absorption region. It is shown that Kerr nonlinearity invert and enhance the subluminal/superluminal behaviors of the pulse and self-Kerr effect is found to be more subluminal/superluminal as compared to cross-Kerr effect. The results show significant applications in i...Physics Letters AjournalsTue, 24 Sep 2019 19:12:28 +0100729725826Comment on “Stabilization of trapless Bose-Einstein condensates without any management” [Phys. Lett. A, 383(17) (2019) 2033-2038]
https://medworm.com/729725825/comment-on-stabilization-of-trapless-bose-einstein-condensates-without-any-management-phys-l/
Publication date: Available online 23 September 2019Source: Physics Letters AAuthor(s): Zhao-Hui Wang, Ji-Xuan HouAbstractA recent paper by T. Ramakrishnan and S. Subramaniyan shows that there is an enhancement of the stability of the trapless BECs due to the inclusion of the higher-order interaction along with the two-and three-body interactions. We point out and correct the erroneous results calculated by the authors concerning the effective potential of the trapless BECs. In addition we have shown that the incorrect expression used by authors leads to notable discrepancies between such results and exact ones. Moreover, our numerical results coincide with our theoretical predictions. (Source: Physics Letters A)Physics Letters AjournalsTue, 24 Sep 2019 19:12:28 +0100729725825Convergence of chaotic attractors due to interaction based on closeness
https://medworm.com/729725824/convergence-of-chaotic-attractors-due-to-interaction-based-on-closeness/
Publication date: Available online 23 September 2019Source: Physics Letters AAuthor(s): Sayantan Nag Chowdhury, Soumen Majhi, Dibakar Ghosh, Awadhesh PrasadAbstractExploration of coherence phenomena in ensembles of interacting dynamical systems has been in the centre of research in social, physical, biological and technological systems for decades. But, in most of the studies, either completely percolated time- and space-static networks or temporal connectivities disregarding the systems' own dynamics have been dealt with. In this work, we examine the correlation between structural and dynamical evolution in networks of interacting dynamical systems. We specifically demonstrate the scenario of convergence of a set of chaotic attractors into a single attractor as a result of sufficient inte...Physics Letters AjournalsTue, 24 Sep 2019 19:12:28 +0100729725824Anisotropic strain effects on light emission characteristics of CdZnO/ZnO quantum well structures
https://medworm.com/729725823/anisotropic-strain-effects-on-light-emission-characteristics-of-cdznozno-quantum-well-structures/
Publication date: Available online 23 September 2019Source: Physics Letters AAuthor(s): Seoung-Hwan ParkAbstractAnisotropic strain effects by strain relaxation on TE-polarized light emission characteristics of c-plane CdZnO/ZnO quantum well (QW) structures were theoretically investigated by using the multiband effective-mass theory. The CdZnO/ZnO QW structure with anisotropic strain has much larger emission intensity than conventional CdZnO/ZnO QW structure without the strain relaxation. In the case of the strain relaxation along x(or y)-direction, the x(or y)-polarized light emission is observed to be larger than the x(or y)-polarized light emission. In particular, in the case of the strain relaxation along both x- and y-directions, the increase in the spontaneous emission peak is signifi...Physics Letters AjournalsTue, 24 Sep 2019 19:12:28 +0100729725823Electronic and transport properties of zigzag-edge monolayer/bilayer phosphorene nanoribbon junctions under a perpendicular electric field
https://medworm.com/728928402/electronic-and-transport-properties-of-zigzag-edge-monolayerbilayer-phosphorene-nanoribbon-junction/
Publication date: Available online 20 September 2019Source: Physics Letters AAuthor(s): Jie Gong, Benhu Zhou, Benliang ZhouAbstractWe study the electronic and transport properties of monolayer/bilayer/bilayer (ML/BL/BL) and monolayer/bilayer/monolayer (ML/BL/ML) zigzag-edge phosphorene nanoribbon (ZPNR) junctions modulated by a perpendicular electric field (PEF). Within the tight-binding model Hamiltonian and by adopting the nonequilibrium Green's function, it is demonstrated that some oscillating conductance plateaus appear for the junctions, and the conductances are suppressed by the applied PEF. Interestingly, the direction of the PEF has different influence on the conductance of both junctions. We further present separately the band structures of the left lead, the central region and r...Physics Letters AjournalsSat, 21 Sep 2019 18:39:49 +0100728928402Enhancement of THz absorption in monolayer graphene for light at Brewster angle incidence
https://medworm.com/728928401/enhancement-of-thz-absorption-in-monolayer-graphene-for-light-at-brewster-angle-incidence/
Publication date: Available online 20 September 2019Source: Physics Letters AAuthor(s): Jun WuAbstractThe enhancement of absorption in graphene for light at Brewster angle incidence is investigated. It is achieved by placing a graphene on a resonant Brewster filter that incorporating a spacer layer. The absorber presents above 50% absorption at resonance, which is attributed to the excitation of guided mode resonances. The electromagnetic field intensity distributions are illustrated to intuitively confirm the physical mechanism of such phenomenon. Moreover, the influence of geometric parameters on absorption is investigated to provide a useful guidance for practical fabrication. Besides, it is found that the absorption properties not only can be controlled by adjusting the incident angle ...Physics Letters AjournalsSat, 21 Sep 2019 18:39:49 +0100728928401Prediction of 2D Li2X (X=Se, Te) monolayer semiconductors by first principles calculations
https://medworm.com/728450839/prediction-of-2d-li2x-xse-te-monolayer-semiconductors-by-first-principles-calculations/
Publication date: Available online 18 September 2019Source: Physics Letters AAuthor(s): Mosayeb Naseri, D.M. HoatAbstractTwo dimensional monolayer materials play important roles in new generation of electronic and optical devices in nano scale. In this paper, by using first principles calculations, the existence of 2D Li2X (X=Se, Te) monolayer materials are theoretically predicted. Through cohesive energy calculation and phonon dispersion simulation, it is proved that the proposed 2D Li2Se and Li2Te monolayer materials are energetically and dynamically stable suggests their potential experimental realization. Our study shows that these newly predicted compounds are direct semiconductors and have strain tunable wide band gaps. As direct semiconductors, these new monolayers may have many app...Physics Letters AjournalsThu, 19 Sep 2019 22:16:13 +0100728450839Electronic properties of novel bismuthene nanosheets with adsorption studies of G-series nerve agent molecules – a DFT outlook
https://medworm.com/728450838/electronic-properties-of-novel-bismuthene-nanosheets-with-adsorption-studies-of-g-series-nerve-agent/
Publication date: Available online 18 September 2019Source: Physics Letters AAuthor(s): R. Bhuvaneswari, V. Nagarajan, R. ChandiramouliAbstractIn order to confirm the ability of bismuthene nanosheet in detecting the G-series nerve agents, electronic and adsorption properties are investigated. The alteration in the band gap is observed (from the energy band structure) upon adsorption of G-series nerve agents, which results in the modification in the conductivity of BiNS. In addition, to establish the potential application of BiNS as a nerve agent sensor, the adsorption energy, average energy gap variation and Bader charge transfer (vital adsorption properties) are evaluated for the nerve agents, which is physisorbed on BiNS. Furthermore, the supreme statement made in the existing research o...Physics Letters AjournalsThu, 19 Sep 2019 22:16:13 +0100728450838Comparing geometric discord and negativity for bipartite states
https://medworm.com/728450837/comparing-geometric-discord-and-negativity-for-bipartite-states/
Publication date: Available online 18 September 2019Source: Physics Letters AAuthor(s): Priyabrata Bag, Santanu Dey, Hiroyuki OsakaAbstractThe geometric discord D of a state is a measure of the quantumness of the state and the negativity N is a measure of the entanglement of a state. It was proved by D. Girolami and G. Adesso that for states on C2⊗C2, the geometric discord is always greater than or equal to the square of the negativity and conjectured that this holds in general. S. Rana and P. Parashar showed that this relation does not hold for all states on C2⊗Cn for n>2. We provide several analytic families of states on C2⊗C3 violating this relation. Certain upper and lower bounds for N2−D are obtained for states on Cm⊗Cn for any m,n∈N. (Source: Physics Letters A)Physics Letters AjournalsThu, 19 Sep 2019 22:16:13 +0100728450837Effect of pressure and temperature on spin-dependent tunneling in InAs/GaAs heterostructure with Dresselhaus spin-orbit interaction
https://medworm.com/728450836/effect-of-pressure-and-temperature-on-spin-dependent-tunneling-in-inasgaas-heterostructure-with-dre/
Publication date: Available online 18 September 2019Source: Physics Letters AAuthor(s): L. Bruno Chandrasekar, M. Karunakaran, K. GnanasekarAbstractUsing the transfer matrix, spin-dependent electron tunneling was studied in InAs/GaAs double barrier symmetrical heterostructure. The effect of Dresselhaus spin-orbit interaction in this system was analysed as a function of pressure and temperature. Both pressure and temperature influences the polarization efficiency, barrier transparency and dwell time of electrons. The increasing pressure increases polarization efficiency, tunneling life time and dwell time of electrons, where as the increasing temperature decreases the same parameters. The results might be helpful for the fabrication of spin-devices. (Source: Physics Letters A)Physics Letters AjournalsThu, 19 Sep 2019 22:16:13 +0100728450836RKKY interaction in the zigzag-edge silicene-like nanoflake
https://medworm.com/728450835/rkky-interaction-in-the-zigzag-edge-silicene-like-nanoflake/
Publication date: Available online 18 September 2019Source: Physics Letters AAuthor(s): Fatemeh Mazhari Mousavi, Rouhollah FarghadanAbstractBy considering the Kane-Mele-Hubbard approximation on the honeycomb lattice, we investigate the spin-spin correlation for two magnetic impurities in zigzag edge silicene-like nanoflake (ZSiLF). The dependence of the spatial behaviors of RKKY interaction on the electron-electron (e-e), intrinsic spin-orbit interactions (ISOI) and, electric field are systematically investigated. Generally, the spatial behaviors of the RKKY interaction sensitively change by changing e-e interaction and electric field strengths in the presence of ISOI. The ISOI in a ZSiLF result in long-range in-plane and Ising interactions. Moreover, e-e interaction induces non-zero Dzyal...Physics Letters AjournalsThu, 19 Sep 2019 22:16:13 +0100728450835Carrier mobility and relaxation time in BiCuSeO
https://medworm.com/728130136/carrier-mobility-and-relaxation-time-in-bicuseo/
Publication date: Available online 17 September 2019Source: Physics Letters AAuthor(s): Jian Liu, Qiao-Yu Jiang, Shi-Da Zhang, Heng ZhangAbstractTo obtain thermoelectric properties of materials, a constant relaxation time approximation is generally employed. By employing deformation potential theory, a derivation of relaxation time and carrier mobility of BiCuSeO system is proposed combining with density functional theory calculation. And the inter-valley scattering, acoustic phonon scattering and ionized impurity scattering were considered in the model. The calculated values of relaxation time and carrier mobility in BiCuSeO are in good agreement with the results of experiment. The results suggest that acoustic phonon scattering is in dominant and the constant relaxation time approximatio...Physics Letters AjournalsWed, 18 Sep 2019 17:09:32 +0100728130136Half-metallicity modulation of zigzag BC2N nanoribbons by transverse electric fields: A first principles study
https://medworm.com/728130135/half-metallicity-modulation-of-zigzag-bc2n-nanoribbons-by-transverse-electric-fields-a-first-princi/
Publication date: Available online 17 September 2019Source: Physics Letters AAuthor(s): Xiaoling Lü, Jimin Huang, Shuhui Lv, Wenyue Dong, Yanwei Li, Yu Shen, Zhenjun Si, Qian Duan, Yisong ZhengAbstractWe performed density functional theory calculations to investigate the electronic and magnetic properties of H-terminated zigzag BC2N nanoribbons (ZBC2NNRs) with the atoms arranged as B-C-N-C along zigzag lines. The ribbons can be classified into three groups according to the profiles of band structures and edge atoms: BN-BN, CC-CC and BN-CC. Among them, CC-CC and BN-CC ZBC2NNRs behave magnetic ground states. The results show that the CC-CC ZBC2NNR is an antiferromagnetic (AFM) semiconductor. Under the transverse electric field, the half-metallicity of 16-CC-CC ZBC2NNR can be achieved with e...Physics Letters AjournalsWed, 18 Sep 2019 17:09:32 +0100728130135Observation of topological valley transport of elastic waves in bilayer phononic crystal slabs
https://medworm.com/728130134/observation-of-topological-valley-transport-of-elastic-waves-in-bilayer-phononic-crystal-slabs/
Publication date: Available online 17 September 2019Source: Physics Letters AAuthor(s): Junrui Jiao, Tinggui Chen, Hongqing Dai, Dejie YuAbstractIn this Letter, we propose a unique bilayer design of phononic crystal slabs that are constructed by two layers of snowflake phononic crystal plates connected by a honeycomb array of cylinders. By tuning orientations of snowflake-shaped holes in both layers, we achieve two kinds of valley-projected topological elastic insulators distinguished by conventional and layer-polarized topological valley Hall phases. Then, between different conventional and layer-polarized topological valley Hall phases, two kinds of edge modes, layer-mixed and layer-polarized edge modes, are obtained and explored. In finite-size samples, the interesting topological trans...Physics Letters AjournalsWed, 18 Sep 2019 17:09:32 +0100728130134Controlled trapping of single particle states on a periodic substrate by deterministic stubbing
https://medworm.com/727969742/controlled-trapping-of-single-particle-states-on-a-periodic-substrate-by-deterministic-stubbing/
We present a case here, where the wells have a hierarchically distribution of widths, hosting standing wave solutions in the thermodynamic limit. (Source: Physics Letters A)Physics Letters AjournalsWed, 18 Sep 2019 02:12:31 +0100727969742Effect of bilayer repeats on magnetic properties of Au-buffered Co/Ni multilayers with perpendicular magnetic anisotropy
https://medworm.com/727969741/effect-of-bilayer-repeats-on-magnetic-properties-of-au-buffered-coni-multilayers-with-perpendicular/
This study provides a deep understanding and effective control of magnetic properties of Co/Ni multilayers for spintronics devices. (Source: Physics Letters A)Physics Letters AjournalsWed, 18 Sep 2019 02:12:31 +0100727969741Confined clustering of AuCu nanoparticles under ambient conditions
https://medworm.com/727969740/confined-clustering-of-aucu-nanoparticles-under-ambient-conditions/
Publication date: Available online 16 September 2019Source: Physics Letters AAuthor(s): O. Rocha-Rocha, M. Cortez-Valadez, G. Calderón-Ayala, C. Martinez-Nuñez, M. Pedroza-Montero, M. Flores-AcostaAbstractThe study of bimetallic clusters has been increasing in recent years due to the wide range of novel applications, when compared with monometallic nanoparticles This paper presents a simple method of low toxicity to obtain bimetallic nanoparticle clusters of AuCu. The localized surface plasmon resonance (LSPR) of the nanoalloy was located in a value in between those reported for AuNP and CuNP. Raman bands of nanoparticle clusters of AuCu were observed in the range 130-300 cm−1. The structural and optical analysis of the synthesized nanoparticles confirmed the presence of the bond Au-Cu...Physics Letters AjournalsWed, 18 Sep 2019 02:12:31 +0100727969740Optical absorption coefficients in asymmetric quantum well
https://medworm.com/727172395/optical-absorption-coefficients-in-asymmetric-quantum-well/
Publication date: Available online 13 September 2019Source: Physics Letters AAuthor(s): Chaojin Zhang, Cong Min, Bo ZhaoAbstractThe optical absorption coefficients considering electron-phonon interaction in asymmetrical quantum wells are theoretically studied. The result shows that the optical absorption coefficients depend strongly on the parameters of quantum well. Interestingly, the theoretical values of the optical absorption coefficients obviously increase with considering the electron-phonon interaction. (Source: Physics Letters A)Physics Letters AjournalsSun, 15 Sep 2019 00:39:24 +0100727172395Border effect corrections for diagonal line based recurrence quantification analysis measures
https://medworm.com/727172394/border-effect-corrections-for-diagonal-line-based-recurrence-quantification-analysis-measures/
Publication date: Available online 13 September 2019Source: Physics Letters AAuthor(s): K. Hauke Kraemer, Norbert MarwanAbstractRecurrence Quantification Analysis (RQA) defines a number of quantifiers, which base upon diagonal line structures in the recurrence plot (RP). Due to the finite size of an RP, these lines can be cut by the borders of the RP and, thus, bias the length distribution of diagonal lines and, consequently, the line based RQA measures. In this letter we investigate the impact of the mentioned border effects and of the thickening of diagonal lines in an RP (caused by tangential motion) on the estimation of the diagonal line length distribution, quantified by its entropy. Although a relation to the Lyapunov spectrum is theoretically expected, the mentioned entropy yields c...Physics Letters AjournalsSun, 15 Sep 2019 00:39:24 +0100727172394Dynamical properties of quasiparticles emerged in a nodal ring optical lattice
https://medworm.com/727172393/dynamical-properties-of-quasiparticles-emerged-in-a-nodal-ring-optical-lattice/
Publication date: Available online 13 September 2019Source: Physics Letters AAuthor(s): Xi-Dan Hu, Yu-Lei Huang, Xin Shen, Kai-Yu Liao, Zhi LiAbstractThe dynamics of nodal ring quasiparticles (NRQPs) has been studied in an optical lattice. By tuning the lattice parameters, one can realize a Lifshits phase transition from a nodal ring semi-metallic to a band insulating phase. For the case where the initial state is a wavepacket, an effective Hamiltonian is obtained to simulate the system's dynamics. Analytical result is explicitly derived with the effective Hamiltonian and the dynamics shows the Zitterbewegung motion. We have analyzed the effects induced by the finite width of the atomic wave packets combined with the consideration of band structure in each phase. (Source: Physics Letters A...Physics Letters AjournalsSun, 15 Sep 2019 00:39:24 +0100727172393Stationary and dynamical properties of one-dimensional quantum droplets
https://medworm.com/727172392/stationary-and-dynamical-properties-of-one-dimensional-quantum-droplets/
Publication date: Available online 13 September 2019Source: Physics Letters AAuthor(s): Sherzod R. Otajonov, Eduard N. Tsoy, Fatkhulla Kh. AbdullaevAbstractThe dynamics of quantum droplets in 1D is analyzed on the basis of the variational approach (VA). It is shown that the VA based on the super-Gaussian function gives a good approximation of stationary states. The period of small oscillations of the perturbed droplet is obtained. It is found numerically that oscillations are almost undamped for many periods. Based on the VA, an existence of stable localized states for different combinations of signs of nonlinearities is demonstrated. (Source: Physics Letters A)Physics Letters AjournalsSun, 15 Sep 2019 00:39:24 +0100727172392Non-autonomous wave solutions for the Gross-Pitaevskii (GP) equation with a parabola external potential in Bose-Einstein condensates
https://medworm.com/727172391/non-autonomous-wave-solutions-for-the-gross-pitaevskii-gp-equation-with-a-parabola-external-potent/
Publication date: Available online 13 September 2019Source: Physics Letters AAuthor(s): Chunping Liu, Fajun Yu, Li LiAbstractA Gross-Pitaevskii (GP) equation with a parabola external potential is considered, and is transformed into a standard nonlinear Schrödinger (NLS) equation. By using the homogeneous balance principle and F-expansion method, we study non-autonomous wave solutions of the GP equation with a parabola external potential. In particular, based on the similarity transformation, several families of non-autonomous wave solutions of the GP equation are presented with snaking behaviors and different amplitude surfaces. These obtained bright-dark soliton solutions can give some potential applications in Bose-Einstein condensates. (Source: Physics Letters A)Physics Letters AjournalsSun, 15 Sep 2019 00:39:24 +0100727172391Computing scalar products via a two-terminal quantum transmission line
https://medworm.com/726851176/computing-scalar-products-via-a-two-terminal-quantum-transmission-line/
Publication date: Available online 12 September 2019Source: Physics Letters AAuthor(s): J. Stolze, A.I. ZenchukAbstractThe scalar product of two vectors with K real components can be computed using two quantum channels, that is, information transmission lines in the form of spin-1/2 XX chains. Each channel has its own K-qubit sender and both channels share a single two-qubit receiver. The K elements of each vector are encoded in the pure single-excitation initial states of the senders. After time evolution, a bi-linear combination of these elements appears in the only matrix element of the second-order coherence matrix of the receiver state. An appropriate local unitary transformation of the extended receiver turns this combination into a renormalized version of the scalar product of the o...Physics Letters AjournalsFri, 13 Sep 2019 19:15:28 +0100726851176Neuron model with conductance-resistance symmetry
https://medworm.com/726851175/neuron-model-with-conductance-resistance-symmetry/
Publication date: Available online 12 September 2019Source: Physics Letters AAuthor(s): Bo DengAbstractThis paper is to derive a mathematical model for neuron by imposing only a principle of symmetry that two modelers must obtain the same model when one models the conductances of ion channels and the other models the channels' resistances. Conductance-voltage characteristics for ion transport channels and protein gating channels are both derived. They are expressed as products of maximal conductances and opening probabilities for both types of channel. It gives an explanation to the role of spontaneous firing of individual channel pores and to the origin of leak current. The model has a better fit to a classical data than the Hodgkin-Huxley model does. It can also be reduced to a 2-dimensi...Physics Letters AjournalsFri, 13 Sep 2019 19:15:28 +0100726851175Pseudomagnetic fields and Landau levels for out-of-plane elastic waves in gradient snowflake-shaped crystals
https://medworm.com/726851174/pseudomagnetic-fields-and-landau-levels-for-out-of-plane-elastic-waves-in-gradient-snowflake-shaped-/
Publication date: Available online 12 September 2019Source: Physics Letters AAuthor(s): Ji-cheng Luo, Lu-yang Feng, Hong-bo Huang, Jiu-jiu ChenAbstractThe study of pseudomagnetic fields (PMF) in classical waves draws a growing attention due to the strength of PMF far higher than real magnetic fields. Here, we show that a giant PMF for out-of-plane elastic waves can be created in the snowflake-shaped crystals by introducing a gradient angle modulation along one direction. In particular, we demonstrate that the Landau energy levels for out-of-plane elastic waves can be formed near the Dirac cone region, as a hallmark of high-field physics induced by PMF. Moreover, the sublattice polarized bulk states similar to the behavior of graphene electron in magnetic fields are achieved in our elastic ...Physics Letters AjournalsFri, 13 Sep 2019 19:15:28 +0100726851174Observation of flux qubit states with the help of a superconducting differential double contour interferometer
https://medworm.com/726851173/observation-of-flux-qubit-states-with-the-help-of-a-superconducting-differential-double-contour-inte/
Publication date: Available online 12 September 2019Source: Physics Letters AAuthor(s): A.V. NikulovAbstractThe critical current of a new structure, the superconducting differential double contour interferometer (DDCI), investigated recently, depends on the parity of the sum of quantum numbers of the two superconducting loops connected in two points by two Josephson junctions. The theory confirms that the DDCI structure can be used for the ideal readout of quantum states of the flux qubit. Large jumps in the critical current and voltage enables to observe continuously the change in time the state of the flux qubit. Such observations can have fundamental importance for the investigation of macroscopic quantum systems with strongly discrete spectrum such as the flux qubit. The DDCI structure...Physics Letters AjournalsFri, 13 Sep 2019 19:15:28 +0100726851173Influence of dilution on magnetization properties of geometrically frustrated magnetic systems: Effective-field theory cluster approximations on kagome lattice
https://medworm.com/726851172/influence-of-dilution-on-magnetization-properties-of-geometrically-frustrated-magnetic-systems-effe/
Publication date: Available online 12 September 2019Source: Physics Letters AAuthor(s): E. Jurčišinová, M. JurčišinAbstractThe influence of the site dilution on the magnetization properties of the antiferromagnetic spin-1/2 Ising model on the kagome lattice is systematically investigated using various n-site cluster effective-field theory approximations up to the cluster size n=12. It is shown that, regardless of the cluster approximation, the site dilution of the system leads, in addition to the existence of the standard saturated ground state, to the formation of four nontrivial plateau ground states together with five single-point ground states that separate them in the zero temperature limit. It is also shown that, while magnetization properties of the saturated ground state and t...Physics Letters AjournalsFri, 13 Sep 2019 19:15:28 +0100726851172Plasmon modes in 3-layer graphene structures: Inhomogeneity effects
https://medworm.com/726690578/plasmon-modes-in-3-layer-graphene-structures-inhomogeneity-effects/
Publication date: Available online 11 September 2019Source: Physics Letters AAuthor(s): Dong Thi Kim Phuong, Nguyen Van MenAbstractWe calculate the plasmon frequency and damping rate in a 3-layer graphene system made of parallel monolayer and bilayer graphene sheets using the random-phase-approximation dielectric function and taking into account the inhomogeneity of the dielectric background of the system. Numerical results show that two out-of-phase acoustic and one in-phase optical plasmon modes can be found from the zeroes of dynamical dielectric function of the structure. Plasmon frequencies and damping rate of plasma oscillations depend significantly on the inhomogeneity of environment, so plamon curves become more distinctive from each other in single-particle excitation region, comp...Physics Letters AjournalsFri, 13 Sep 2019 04:13:24 +0100726690578Surface acoustic waves in 2D-phononic crystal of laminated pillars on a semi-infinite ZnO substrate
https://medworm.com/726690577/surface-acoustic-waves-in-2d-phononic-crystal-of-laminated-pillars-on-a-semi-infinite-zno-substrate/
Publication date: Available online 11 September 2019Source: Physics Letters AAuthor(s): Tengjiao Jiang, Chunlei Li, Qiang HanAbstractIn this paper a phononic crystal of laminated pillars which are composed of two materials on a semi-infinite ZnO substrate is proposed. The unit cell can be regarded as a double-resonator model, which explicates the variation of band gaps. It is revealed that the band structure of the PC is highly influenced by the proportion of PZT-4 in laminated pillars. Besides, the high-frequency band gaps are the result of combined actions of the local resonance and the Bragg scattering, and the former dominates. Furthermore, the influences of the structural damping are investigated. It is observed that the bandgap-ratio remain unchanged and the band gaps translate to th...Physics Letters AjournalsFri, 13 Sep 2019 04:13:24 +0100726690577Conventional and rotating magnetoelectric effect of a half-filled spin-electron model on a doubly decorated square lattice
https://medworm.com/726370357/conventional-and-rotating-magnetoelectric-effect-of-a-half-filled-spin-electron-model-on-a-doubly-de/
Publication date: Available online 10 September 2019Source: Physics Letters AAuthor(s): Hana Čenčariková, Jozef StrečkaAbstractA conventional and rotating magnetoelectric effect of a half-filled spin-electron model on a doubly decorated square lattice is investigated by exact calculations. An importance of the electron hopping and spatial orientation of the electric field upon a magnetoelectric effect is examined in detail. A critical temperature may display one or two consecutive round maxima as a function of the electric field. Although the rotating magnetoelectric effect (RME) does not affect the ground-state ordering, the pronounced RME is found close to a critical temperature of continuous phase transition. It is shown that RME is amplified upon strengthening of the electric field...Physics Letters AjournalsWed, 11 Sep 2019 23:39:36 +0100726370357Stress generation during anisotropic lithiation in silicon nanopillar electrodes: A reactive force field study
https://medworm.com/726370356/stress-generation-during-anisotropic-lithiation-in-silicon-nanopillar-electrodes-a-reactive-force-f/
Publication date: Available online 10 September 2019Source: Physics Letters AAuthor(s): Luoxia Cao, Hui Yang, Feifei FanAbstractModels that are developed to investigate lithiation-induced stress in high-volume-change electrodes are often based on continuum approaches with simplifying assumptions. In this work, we investigate stress generation during the first lithiation of crystalline silicon electrodes solely using atomistic simulations with chemo-mechanical fidelity. We use a <100>-oriented silicon nanopillar as a model system and perform molecular statics simulations with a reactive force field. The simulation approach incorporates the key physical feature of the lithiation – anisotropic formation and migration of an atomistically-sharp phase boundary. The resulting stress fields ...Physics Letters AjournalsWed, 11 Sep 2019 23:39:36 +0100726370356Structural and electronic properties of armchair graphene nanoribbons functionalized with fluorine
https://medworm.com/726051368/structural-and-electronic-properties-of-armchair-graphene-nanoribbons-functionalized-with-fluorine/
Publication date: Available online 9 September 2019Source: Physics Letters AAuthor(s): Kamal K. Jha, Neha Tyagi, Neeraj K. Jaiswal, Pankaj SrivastavaAbstractThe interaction of armchair graphene nanoribbons (AGNR) with F has been investigated by considering it as a passivating element as well as adatom impurity. The adsorption of F at three different sites viz. bridge (B), top (T) and hole (H) is examined to determine the most stable configuration. It is revealed that F passivation is slightly more favorable than the H passivation of AGNR and it also affects the band gap. Interestingly, F adsorbed AGNR exhibit magnetic ground state which is about 70 meV more favourable over nonmagnetic state. Further, F passivated AGNR exhibit linear I-V characteristic which indicates potential for intercon...Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051368Darboux transformation and soliton solutions of the semi-discrete massive Thirring model
https://medworm.com/726051367/darboux-transformation-and-soliton-solutions-of-the-semi-discrete-massive-thirring-model/
Publication date: Available online 9 September 2019Source: Physics Letters AAuthor(s): Tao Xu, Dmitry E. PelinovskyAbstractA one-fold Darboux transformation between solutions of the semi-discrete massive Thirring model is derived using the Lax pair and dressing methods. This transformation is used to find the exact expressions for soliton solutions on zero and nonzero backgrounds. It is shown that the discrete solitons have the same properties as solitons of the continuous massive Thirring model. (Source: Physics Letters A)Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051367Thermospin effects in a T-shaped spin valves with spin-flip scattering
https://medworm.com/726051366/thermospin-effects-in-a-t-shaped-spin-valves-with-spin-flip-scattering/
Publication date: Available online 9 September 2019Source: Physics Letters AAuthor(s): Li Xu, Caili Zhang, Yanfang HuangAbstractWith the help of the nonequilibrium Green's function technique, we theoretically analyze the thermospin property through a typical T-shaped spin valve with spin-flip scattering in the linear regime. The influences of spin-flip coefficient of interdot λ, spin-flip coefficient of intradot η and interdot hopping coefficient t+δσΔt on thermospin property are discussed. As interdot hopping coefficient t is equal to energy level ε, the spectrum of Gs shows Fano-like effect with ε variation. Antiresonance position of Gs is almost unchanged and its width becomes narrower with ε increasing. Spin thermopower Ss is close to the maximum of the peak and charge thermopo...Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051366Stabilization of E-type antiferromagnetic ordering in La and Y substituted orthorhombic LuMnO3: A first-principles study
https://medworm.com/726051365/stabilization-of-e-type-antiferromagnetic-ordering-in-la-and-y-substituted-orthorhombic-lumno3-a-fi/
Publication date: Available online 9 September 2019Source: Physics Letters AAuthor(s): Sathya Sheela Subramanian, Sambandam Anandan, Baskaran NatesanAbstractWe carry out first principles density functional theory calculations of non-lone pairs, namely, La and Y substituted orthorhombic LuMnO3, to verify the generality of symmetry breaking effects observed in the lone pair cations substituted orthorhombic rare earth manganites. Our calculations revealed that similar to lone pair cations ordering at the A-site of LuMnO3, non-lone pair cations ordering also results in the lowering of the symmetry thereby proving that the symmetry breaking with A-site ordering is a generic effect. Interestingly, we were able to stabilize the large radius La substituted LuMnO3 into an E-type antiferromagnetic (...Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051365Exactly solvable chain of interacting electrons with correlated hopping and pairing
https://medworm.com/726051364/exactly-solvable-chain-of-interacting-electrons-with-correlated-hopping-and-pairing/
Publication date: Available online 9 September 2019Source: Physics Letters AAuthor(s): Igor N. KarnaukhovAbstractA generalization of the Mattis-Nam model Mattis and Nam (1972) [7], which takes into account a correlated hopping and pairing of electrons, is proposed, its exact solution is obtained. In the framework of the model the stability of the zero energy Majorana fermions localized at the boundaries is studied in the chain in which electrons interact through both the on-site Hubbard interaction and the correlated hopping and pairing. The ground-state phase diagram of the model is calculated, the region of existence of topological states is determined. It is shown that low-energy excitations destroy bonds between electrons in the chain, leading to an insulator state. (Source: Physics Le...Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051364Superalkali NM4 (M = Li, Na, K): Stabilities and electronic structures
https://medworm.com/726051363/superalkali-nm4-mli-na-k-stabilities-and-electronic-structures/
Publication date: Available online 9 September 2019Source: Physics Letters AAuthor(s): Zhaoyan Zhang, Hongshan ChenAbstractSuperatoms are clusters that mimic the chemistry of atoms and new materials with unique properties can be synthesized from them. Superalkali NM4 clusters with homo- and hetero-alkalis M = Li, Na, K are designed, and their vertical ionization potentials (3.22 ∼ 3.74 eV) are lower than that of Cs atom. The stabilities of the superalkalis are guaranteed by the binding energies and positive energies of the dissociation channel NM3 + M, and NLi4 is the most stable among the NM4 clusters. The high stability and tetrahedral geometry make these species idea units for building new materials. (Source: Physics Letters A)Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051363Planar metamaterial analogue of electromagnetically induced transparency for a miniature refractive index sensor
https://medworm.com/726051362/planar-metamaterial-analogue-of-electromagnetically-induced-transparency-for-a-miniature-refractive-/
Publication date: Available online 9 September 2019Source: Physics Letters AAuthor(s): Rong Li, Xiang-kun Kong, Shao-bin Liu, Zhi-ming Liu, Yu-meng LiAbstractA planar metamaterial of analogue of Electromagnetically Induced Transparency (EIT-like) is theoretically and experimentally investigated. The EIT-like metamaterial unit cell, whose electrical size is only 0.2λ0, consists of a split ring resonator (SRR) and a folded-line pair resonator (FLPR). For the TM wave incidence, a sharp transmitted peak with high quality factor can be observed. The EIT-like metamaterial is fabricated and measured. Good agreement is obtained between the simulation and measurement results. A miniature refractive index sensor based on the proposed metamaterial is simulated and exhibits high sensitivity and Figur...Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051362Electron-phonon coupling in armchair silicene nanoribbons
https://medworm.com/726051361/electron-phonon-coupling-in-armchair-silicene-nanoribbons/
We report the effects of electron-phonon coupling on the charge density distribution of polarons in armchair nanoribbons of silicene by using an extended tight-binding model with lattice relaxation. The results show that the charge distribution in silicene nanoribbons is analogous to graphene and that the charge localization increases when the intensity of electron-phonon coupling also increases. We further show that silicene nanoribbons may be a conducting or semiconducting material, depending on both the width of the nanoribbon and the possibility of polaron formation. This contribution provides additional insight into the behavior of polarons in silicene nanoribbons, systems of great interest. (Source: Physics Letters A)Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051361Editors
https://medworm.com/726051360/editors/
Publication date: 25 October 2019Source: Physics Letters A, Volume 383, Issue 30Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051360Retraction notice to “Co-thickness and oxidation states effect on magnetic anisotropy in Co/MgO heterostructure” [Phys. Lett. A 383 (2019) 1977–1982]
https://medworm.com/726051347/retraction-notice-to-co-thickness-and-oxidation-states-effect-on-magnetic-anisotropy-in-comgo-he/
Publication date: 25 October 2019Source: Physics Letters A, Volume 383, Issue 30Author(s): S. Nazir (Source: Physics Letters A)Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051347Editors
https://medworm.com/726051345/editors/
Publication date: 7 November 2019Source: Physics Letters A, Volume 383, Issue 31Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 10 Sep 2019 18:15:30 +0100726051345Potential algebra approach to quantum mechanics with generalized uncertainty principle
https://medworm.com/725259018/potential-algebra-approach-to-quantum-mechanics-with-generalized-uncertainty-principle/
Publication date: Available online 6 September 2019Source: Physics Letters AAuthor(s): Satoshi Ohya, Pinaki RoyAbstractIn this note, we study the potential algebra for several models arising out of quantum mechanics with generalized uncertainty principle. We first show that the eigenvalue equation corresponding to the momentum-space HamiltonianH=−(1+βp2)ddp(1+βp2)ddp+g(g−1)β2p2−gβ, which is associated with some one-dimensional models with minimal length uncertainty, can be solved by the unitary representations of the Lie algebra su(2) if g∈{12,1,32,2,⋯}. We then apply this result to spectral problems for the non-relativistic harmonic oscillator as well as the relativistic Dirac oscillator in the presence of a minimal length and show that these problems can be solved solely in...Physics Letters AjournalsSat, 07 Sep 2019 17:36:33 +0100725259018First-principles studies of graphene antidot lattices on monolayer h-BN substrate
https://medworm.com/725259017/first-principles-studies-of-graphene-antidot-lattices-on-monolayer-h-bn-substrate/
Publication date: Available online 6 September 2019Source: Physics Letters AAuthor(s): Zeng-Xin Wei, Gui-Bin LiuAbstractThe structures and electronic structures of hetero bilayers composed of graphene antidot lattice (GAL) on monolayer h-BN substrate are studied in first-principles method. Bond lengths, interlayer distances, flatness, biaxial strain effects, and effects of translating the GAL layer are studied and analyzed in detail. Results show that introducing a monolayer BN substrate makes the zero-bandgap 5×5 GAL open a bandgap up to 28 meV, while it makes the semiconducting 6×6 GAL keep its low-energy electronic structure almost intact except a small bandgap change by tens of meV at most. Our studies demonstrate that h-BN is a promising substrate for GAL. (Source: Physics Letters A...Physics Letters AjournalsSat, 07 Sep 2019 17:36:33 +0100725259017Electronic and structural properties of black phosphorene doped with Si, B and N
https://medworm.com/725259016/electronic-and-structural-properties-of-black-phosphorene-doped-with-si-b-and-n/
Publication date: Available online 6 September 2019Source: Physics Letters AAuthor(s): Luiza Goulart, Liana Fernandes, Cláudia Lange, Jussane RossatoAbstractThe electronic and structural properties of substitutional and doped phosphorene with B, N and Si were studied using first principles calculations based on density functional theory. Moreover, electronic and structural properties of functionalized phosphorene slowly increasing the concentration of doping was investigated. Phosphorene strongly binds with doped functionalization; B doped phosphorene is the most stable configuration studied. Si doped phosphorene maintains the semiconductor characteristic. B and N doped phosphorene present n-type and p-type semiconductors, respectively. Doped phosphorene with odd number of Si is a semicon...Physics Letters AjournalsSat, 07 Sep 2019 17:36:33 +0100725259016Editors
https://medworm.com/725258999/editors/
Publication date: 15 October 2019Source: Physics Letters A, Volume 383, Issue 29Author(s): (Source: Physics Letters A)Physics Letters AjournalsSat, 07 Sep 2019 17:36:33 +0100725258999Ordering induced transformation from high-entropy to Heusler CrVTiAl alloy
https://medworm.com/724941773/ordering-induced-transformation-from-high-entropy-to-heusler-crvtial-alloy/
Publication date: Available online 5 September 2019Source: Physics Letters AAuthor(s): Peiyu Cao, Hanyue Zhao, Shanshan Liu, Fuyang Tian, Yandong WangAbstractThe equimolar quaternary CrVTiAl is not only a potential spin filter, but also a light-weight high entropy alloy. The excellent performance strongly depends on the order degree. We use the ab initio calculation to investigate the structural, magnetic, elastic properties of CrVTiAl as a function of the order degree describing phase from full disorder A2 to DO3, B2, and L21 to full order Y-type (LiMgPdSn-type) structure. The Cr-Al bonding plays a key role in the local magnetic moments, further induces the increasing lattice parameter and decreasing elastic constants. Furthermore, the effect of preferred sites on mechanical properties is...Physics Letters AjournalsFri, 06 Sep 2019 13:15:26 +0100724941773Vacancy-defect effect on the electronic and optical properties of Pmm2 BC2N: A first-principles study
https://medworm.com/724941772/vacancy-defect-effect-on-the-electronic-and-optical-properties-of-pmm2-bc2n-a-first-principles-stud/
Publication date: Available online 5 September 2019Source: Physics Letters AAuthor(s): Xiong Li, Yan Zhu, Can HuangAbstractOrthorhombic-Pmm2-BC2N as a superhard photocatalyst simulates great interests in the researches of materials-design and application. To promote the studies of Pmm2 BC2N as a multifunctional material with both great hardness and good optical properties, we investigated the electronic and optical properties of Pmm2 BC2N with various vacancy-defects by the systematic first-principles density functional theory (DFT) calculations in this work. The absorption, refractivity, reflectivity, and photoconductivity of considered structures were calculated and explored. The various characteristics of the optical properties were analyzed based on relative computed density of states ...Physics Letters AjournalsFri, 06 Sep 2019 13:15:26 +0100724941772Controlling decoherence via PT-symmetric non-Hermitian open quantum systems
https://medworm.com/724470644/controlling-decoherence-via-pt-symmetric-non-hermitian-open-quantum-systems/
Publication date: Available online 3 September 2019Source: Physics Letters AAuthor(s): Sanjib Dey, Aswathy Raj, Sandeep K. GoyalAbstractWe have studied the effect of a non-Hermitian Bosonic bath on the dynamics of a two-level spin system. The non-Hermitian Hamiltonian of the bath is chosen such that it converges to the harmonic oscillator Hamiltonian when the non-Hermiticity is switched off. We calculate the dynamics of the spin system and found that the non-Hermiticity can have positive as well as negative effects on the coherence of the system. However, the decoherence can be completely eliminated by choosing the non-Hermiticity parameter and the phase of the system bath interaction appropriately. We have also studied the effect of this bath on the entanglement of a two-spin system when ...Physics Letters AjournalsWed, 04 Sep 2019 18:03:26 +0100724470644Discrete and generalized phase space techniques in critical quantum spin chains
https://medworm.com/724470643/discrete-and-generalized-phase-space-techniques-in-critical-quantum-spin-chains/
Publication date: Available online 3 September 2019Source: Physics Letters AAuthor(s): Zakaria Mzaouali, Steve Campbell, Morad El BazAbstractWe apply the Wigner function formalism from quantum optics via two approaches, Wootters' discrete Wigner function and the generalized Wigner function, to detect quantum phase transitions in critical spin-12 systems. We develop a general formula relating the phase space techniques and the thermodynamical quantities of spin models, which we apply to single, bipartite and multi-partite systems governed by the XY and the XXZ models. Our approach allows us to introduce a novel way to represent, detect, and distinguish first-, second- and infinite-order quantum phase transitions. Furthermore, we show that the factorization phenomenon of the XY model is only...Physics Letters AjournalsWed, 04 Sep 2019 18:03:26 +0100724470643Editors
https://medworm.com/724470627/editors/
Publication date: 5 October 2019Source: Physics Letters A, Volume 383, Issue 28Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 04 Sep 2019 18:03:26 +0100724470627The dynamics of two coupled Van der Pol oscillators with attractive and repulsive coupling
https://medworm.com/724154677/the-dynamics-of-two-coupled-van-der-pol-oscillators-with-attractive-and-repulsive-coupling/
Publication date: Available online 2 September 2019Source: Physics Letters AAuthor(s): Shiva Dixit, Amit Sharma, Manish Dev ShrimaliAbstractWe consider a variant of two coupled Van der Pol oscillators with both attractive and repulsive mean-field interactions. In the presence of attractive coupling, the system is in the complete synchrony, while repulsive coupling shows anti-synchronization state leading to suppression of oscillations with increasing interaction strength. The coupled system with both attractive and repulsive interactions shows competitive tendencies of being complete synchronization and anti-synchronization resulting in the stabilization of the fixed point. We have also studied the effect of the damping coefficient of the VdP oscillator on the nature of the transition from...Physics Letters AjournalsTue, 03 Sep 2019 13:15:28 +0100724154677Tunable double-beam optical bistability in an asymmetric double quantum-well system
https://medworm.com/723520633/tunable-double-beam-optical-bistability-in-an-asymmetric-double-quantum-well-system/
Publication date: Available online 30 August 2019Source: Physics Letters AAuthor(s): Yu-Yuan Chen, Ya-Nan Li, Ren-Gang Wan, Hong-Wei YanAbstractWe have proposed a scheme for double-beam optical bistability in a tunnel-coupled asymmetric double quantum-well driven by two optical fields circulating inside two independently unidirectional ring cavities. In contrast to the single-cavity case where single-photon saturated absorption and self Kerr-nonlinearity are dominant, the two-photon absorption and cross phase modulation can be enhanced via tunneling induced interference and have an important influence to the formation of bistability. The bistable behavior can be controlled effectively via the system parameters such as the input and detuning of control field, the detuning of the probe field...Physics Letters AjournalsSun, 01 Sep 2019 05:03:32 +0100723520633Optical reflection properties for the interface associated with Chern insulator and chiral metamaterial
https://medworm.com/723520632/optical-reflection-properties-for-the-interface-associated-with-chern-insulator-and-chiral-metamater/
Publication date: Available online 30 August 2019Source: Physics Letters AAuthor(s): Ran Zeng, Fangfang Chen, Chi Wang, Mingyue Zhang, Haozhen Li, Qiliang Li, Jun Ou, Yaping Yang, Shiyao ZhuAbstractBased on the topological nature of Chern insulator and magnetoelectric coupling of chiral metamaterial, we investigate the electrodynamics for the interface associated with the two media. The Fresnel coefficients of the interface between Chern insulator and chiral metamaterial, as well as the corresponding polarization rotation angles, are derived. The reflection characteristics of the linearly polarized incident wave at the interface, such as complete polarization conversion and change of polarization state, are discussed. Under the combined influence of Chern insulator and chiral metamaterial,...Physics Letters AjournalsSun, 01 Sep 2019 05:03:32 +0100723520632Synchronization in a multiplex network of gene oscillators
https://medworm.com/723202488/synchronization-in-a-multiplex-network-of-gene-oscillators/
Publication date: Available online 29 August 2019Source: Physics Letters AAuthor(s): Abdul Jalil M. Khalaf, Fawaz E. Alsaadi, Fuad E. Alsaadi, Viet-Thanh Pham, Karthikeyan RajagopalAbstractStudy of the synchronization in the network of gene oscillator network has vital importance in understanding of rhythmicity of molecular and cellular activities. In this paper, we analyze a network of linearly coupled genetic oscillators in a multiplex structure. The coupling strength values are changed and the coupling range is considered to be fixed, but different in the two layers. The analyses are done in two cases of periodic and chaotic oscillations. By computing the statistical measures, the interlayer and intralayer synchronization states are studied. The results show that the layer with higher c...Physics Letters AjournalsSat, 31 Aug 2019 00:15:30 +0100723202488Noether symmetry for fractional Hamiltonian system
https://medworm.com/723202487/noether-symmetry-for-fractional-hamiltonian-system/
Publication date: Available online 29 August 2019Source: Physics Letters AAuthor(s): C.J. SongAbstractFractional Hamiltonian systems within combined Riemann-Liouville fractional order derivative and combined Caputo fractional order derivative are established. Then Noether quasi-symmetry and conserved quantity for the fractional Hamiltonian systems are presented. Thirdly, perturbation to Noether quasi-symmetry and adiabatic invariant are studied. Several special cases are discussed in each section. And finally, two applications, i.e., the fractional Lotka biochemical oscillator model and the fractional isotropic harmonic oscillator model, are discussed to illustrate the results and methods. (Source: Physics Letters A)Physics Letters AjournalsSat, 31 Aug 2019 00:15:30 +0100723202487Evolution of breathers and interaction between high-order lump solutions and N-solitons (N → ∞) for Breaking Soliton system
https://medworm.com/723202486/evolution-of-breathers-and-interaction-between-high-order-lump-solutions-and-n-solitons-n/
Publication date: Available online 29 August 2019Source: Physics Letters AAuthor(s): Wei TanAbstractBy employing the Hirota's bilinear method and different test functions, we investigate different forms of breather solitons and some new lump solutions of the (2+1)-dimensional Breaking Soliton system. During this process, some new nonlinear phenomena, such as degeneration of breather solitons, evolution of double breathers and emergence of lump solutions, are studied and shown. Besides, some interaction solutions between high-order lump solutions and N-soliton solutions (N→∞) are studied. We construct the existence theorem of the interaction solutions and give a detailed proof process for the first time. Some different types of interaction solutions are used as concrete examples to illu...Physics Letters AjournalsSat, 31 Aug 2019 00:15:30 +0100723202486Enhanced acoustic localization in the two-dimensional phononic crystals with slit tube defect
https://medworm.com/723202485/enhanced-acoustic-localization-in-the-two-dimensional-phononic-crystals-with-slit-tube-defect/
Publication date: Available online 29 August 2019Source: Physics Letters AAuthor(s): Xiao-peng Wang, Hui Sun, Tian-ning Chen, Xing-guo WangAbstractIn this paper, the acoustic localization characteristics of the two-dimensional phononic crystals with slit tube defect are investigated theoretically and experimentally. In contrast to the typical formation pattern of defect states, the proposed defect states are created by replacing a slotted tube in the center of perfect phononic crystal. Compared to perfect phononic crystal, the proposed structure can effectively localize waves of specific frequencies in the point defect and improve the acoustic pressure amplification. Then the effects of the geometric parameters of the slotted tube on the acoustic localization characteristics are studied. N...Physics Letters AjournalsSat, 31 Aug 2019 00:15:30 +0100723202485High pressure synthesis and thermoelectric performances of Cu2Se compounds
https://medworm.com/723202484/high-pressure-synthesis-and-thermoelectric-performances-of-cu2se-compounds/
Publication date: Available online 29 August 2019Source: Physics Letters AAuthor(s): Lisha Xue, Chao Fang, Weixia Shen, Manjie Shen, Wenting Ji, Yuewen Zhang, Zhuangfei Zhang, Xiaopeng JiaAbstractThe Cu2Se samples were synthesized by high pressure directly at room temperature in several minutes. The composition evolution under high pressure demonstrates that the critical conditions to synthesize Cu2Se are the pressure of 1 GPa and the reaction time of 5 min. The synthetic pressure can effectively tune the morphology, carrier concentration and the electrical transport properties. The low lattice thermal conductivity less than 0.5 Wm−1 K−1 is obtained because of the intrinsic superionic character and the microstructures by high pressure including abundant micropores and lattice defe...Physics Letters AjournalsSat, 31 Aug 2019 00:15:30 +0100723202484First-principles study of two-dimensional van der Waals heterostructure based on ZnO and Mg(OH)2: a potential photocatalyst for water splitting
https://medworm.com/722884715/first-principles-study-of-two-dimensional-van-der-waals-heterostructure-based-on-zno-and-mgoh2-a-/
In this study, the structural, electronic and optical properties of the two-dimensional heterostructure based on ZnO and Mg(OH)2 are investigated by first-principle calculations. The ZnO/Mg(OH)2 heterostructure, formed by van der Waals (vdW) interaction, possesses a type-II band structure, which can separate the photogenerated electron–holes constantly. The heterostructure has decent band edge positions for the redox reaction to decompose the water at pH 0 and 7. As for the interfacial properties of the heterostructure, the trend of band bending of the ZnO and Mg(OH)2 layers in the heterostructure is addressed, which will result a built-in electric field. Besides, the charge-density difference and potential drop across the interface of the ZnO/Mg(OH)2 vdW heterostructure are also calcula...Physics Letters AjournalsThu, 29 Aug 2019 20:03:26 +0100722884715Beat-like frequency pattern of extraordinary transmission and reflection in PT-symmetric Fibonacci aperiodic optical networks of waveguide rings
https://medworm.com/722884714/beat-like-frequency-pattern-of-extraordinary-transmission-and-reflection-in-pt-symmetric-fibonacci-a/
Publication date: Available online 28 August 2019Source: Physics Letters AAuthor(s): Jiaye WuAbstractIn parity-time-symmetric (PT-symmetric) Fibonacci ordered-aperiodic optical networks of waveguide rings, the beat-like pattern of the frequencies corresponding to maximum extraordinary transmission and reflection is investigated. It is found that, resembling acoustic resonance and optical beat, when these frequencies between two contiguous Fibonacci generations are sufficiently close and within a certain limit, the transmission and reflection of the following generation become stronger than those of the previous two; otherwise, they are weakened. These properties are the combined results of the optical PT symmetry and the inherent self-repeating pattern of the Fibonacci ordering, which migh...Physics Letters AjournalsThu, 29 Aug 2019 20:03:26 +0100722884714The higher-order nonlinear Schrödinger equation with non-zero boundary conditions: Robust inverse scattering transform, breathers, and rogons
https://medworm.com/722562183/the-higher-order-nonlinear-schrdinger-equation-with-non-zero-boundary-conditions-robust-inverse-s/
Publication date: Available online 27 August 2019Source: Physics Letters AAuthor(s): Shuyan Chen, Zhenya YanAbstractAn integrable three-parameter fifth-order nonlinear Schrödinger equation with non-zero boundary conditions was studied staring from its Lax pair and a robust inverse scattering transform such that one-, and n-fold modified Darboux transforms (DTs) are presented. For distinct parameters, the one-fold DT is used to simultaneously investigate its first- and second-order breathers, rational W-shaped soliton-like solutions, and rogons. Moreover, we also analyze their wave structures, and relations between these solutions and special parameters. The n-fold DT is also established for the fifth-order NLS equation such that its (2n−1,2n)th-order rogue wave solutions can be found si...Physics Letters AjournalsWed, 28 Aug 2019 15:12:30 +0100722562183How water makes graphene metallic
https://medworm.com/722562182/how-water-makes-graphene-metallic/
Publication date: Available online 27 August 2019Source: Physics Letters AAuthor(s): Michael Hernández, Alejandro Cabo Montes de Oca, Maurice Oliva-Leyva, Gerardo G. NaumisAbstractA simple explanation is given on the tendency of graphene to become metallic when the amount of doped water is increased, an effect which was previously obtained from ab initio band calculations. It is clarified how the effect is mainly determined by oriented water electric dipoles, which create a step like potential at the separation distance between graphene and water planes. By using perturbation theory and an effective potential coupled with a image-charge tail potential, we showed that under increasing the water doping, the lowest energy free band in graphene starts lowering their energies by approaching to...Physics Letters AjournalsWed, 28 Aug 2019 15:12:30 +0100722562182Quantum coherence and entanglement partitions for two driven quantum dots inside a coherent micro cavity
https://medworm.com/722562181/quantum-coherence-and-entanglement-partitions-for-two-driven-quantum-dots-inside-a-coherent-micro-ca/
Publication date: Available online 27 August 2019Source: Physics Letters AAuthor(s): A.-B.A. Mohamed, H. Eleuch, C.H. Raymond OoiAbstractWe explore the coherence and entanglement of two separated quantum dots placed in an open microcavity. The generated entanglement and coherence depend crucially on the two-exciton decay and the initial coherence intensity. The phenomena of sudden death and sudden birth entanglement are observed. (Source: Physics Letters A)Physics Letters AjournalsWed, 28 Aug 2019 15:12:30 +0100722562181Prediction of a new direct-gap silicon phase: T36 silicon
https://medworm.com/722401620/prediction-of-a-new-direct-gap-silicon-phase-t36-silicon/
Publication date: Available online 26 August 2019Source: Physics Letters AAuthor(s): Chun-Xiang Zhao, Yang Huang, Jia-Qi Wang, Chun-Yao Niu, Yu JiaAbstractElemental silicon plays an extremely important role in technologically relevant fields. Owing to its abundance, silicon is the preferred solar-cell materials in spite of the fact that many silicon allotropes have indirect band gaps. Looking for silicon materials with direct band gap is still a significant field in material science. Here, we propose a new silicon allotrope possessing a tetragonal cell with 36 silicon atoms (termed as T36 silicon), which displays P42nmc symmetry. By first-principles calculations, we have systematically studied the structural stabilities, electronic and optical properties of this novel silicon. Our calculat...Physics Letters AjournalsWed, 28 Aug 2019 00:36:25 +0100722401620NaB6Si: A novel wide band gap semiconductor with great hardness
https://medworm.com/721602432/nab6si-a-novel-wide-band-gap-semiconductor-with-great-hardness/
This study provides a fundamental understanding of the structural, mechanical, and electronic properties in NaB6Si. (Source: Physics Letters A)Physics Letters AjournalsSun, 25 Aug 2019 02:03:28 +0100721602432Three-dimensional static analysis of multilayered one-dimensional orthorhombic quasicrystal spherical shells with the piezoelectric effect
https://medworm.com/721602431/three-dimensional-static-analysis-of-multilayered-one-dimensional-orthorhombic-quasicrystal-spherica/
Publication date: Available online 23 August 2019Source: Physics Letters AAuthor(s): Yunzhi Huang, Yang Li, Liangliang Zhang, Han Zhang, Yang GaoAbstractThe static analysis of multilayered one-dimensional orthorhombic piezoelectric quasicrystals spherical shells is presented by using the state vector method. Based on two separated state equations, the solution of a homogenous spherical shell is derived, and the solution for the corresponding multilayered case is obtained via the propagator matrix method. Mechanical behaviors of spherical shells subjected to two kinds of symmetric loads are analyzed, respectively. Under uniformed loads, smaller phonon displacements are achieved in a quasicrystal-skin structure than those in crystal-skin one. Under the compression of rigid half-plane, the ra...Physics Letters AjournalsSun, 25 Aug 2019 02:03:28 +0100721602431Editors
https://medworm.com/721282135/editors/
Publication date: 22 September 2019Source: Physics Letters A, Volume 383, Issue 27Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 23 Aug 2019 20:39:40 +0100721282135Localization of optical pulses in guided wave structures with only fourth order dispersion
https://medworm.com/720490500/localization-of-optical-pulses-in-guided-wave-structures-with-only-fourth-order-dispersion/
Publication date: Available online 19 August 2019Source: Physics Letters AAuthor(s): Wesley B. CardosoAbstractInspired by the recent realization of pure-quartic solitons [Nat. Commun. 7 (2016) 10427], in the present work we study the localization of optical pulses in a similar system, i.e., a silicon photonic crystal air-suspended structure with a hexagonal lattice. The propagation of ultrashort pulses in such a system is well described by a generalized nonlinear Schrödinger (NLS) equation, which in certain conditions works with near-zero group-velocity dispersion and third order dispersion. In this case, the NLS equation has only the fourth order dispersion term. In the present model, we introduce a quasiperiodic linear coefficient that is responsible to induce the localization. The exis...Physics Letters AjournalsTue, 20 Aug 2019 19:15:26 +0100720490500Editors
https://medworm.com/720490470/editors/
Publication date: 12 September 2019Source: Physics Letters A, Volume 383, Issue 26Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 20 Aug 2019 19:15:26 +0100720490470Introducing article numbering to Physics Letters A
https://medworm.com/720490469/introducing-article-numbering-to-physics-letters-a/
Publication date: 12 September 2019Source: Physics Letters A, Volume 383, Issue 26Author(s): Thomas Thayer (Source: Physics Letters A)Physics Letters AjournalsTue, 20 Aug 2019 19:15:26 +0100720490469Quantum diffraction of position-momentum entangled photons from a sharp edge
https://medworm.com/719704669/quantum-diffraction-of-position-momentum-entangled-photons-from-a-sharp-edge/
Publication date: Available online 16 August 2019Source: Physics Letters AAuthor(s): Samridhi Gambhir, Mandip SinghAbstractIn this paper, an experiment of quantum diffraction of position-momentum entangled photons from a straight sharp edge is presented. Path of a single photon of an entangled pair is partially blocked by a sharp edge whereas the other photon is detected at a stationary location without revealing the which-path information of the other photon. Quantum diffraction pattern of the sharp edge is revealed only in the correlated conditional detection of spatially separated photons. Theoretical analysis of the quantum diffraction of position-momentum entangled photons from a sharp edge is also presented in this paper. Experimental measurements of the quantum diffraction pattern a...Physics Letters AjournalsSat, 17 Aug 2019 20:09:21 +0100719704669Broad range frequency – temperature response of Ba2Zn2Fe12O22
https://medworm.com/719072294/broad-range-frequency-temperature-response-of-ba2zn2fe12o22/
Publication date: Available online 14 August 2019Source: Physics Letters AAuthor(s): Bibhuti B. Sahu, S.K. Patri, Banarji BeheraAbstractBa2Zn2Fe12O22 was synthesized by solid state reaction technique. The strongly temperature and frequency dependent electrical properties and complex impedance spectroscopy were analysed. Complex modulus formalism shows the existence of high resistance and small capacitance of the materials for the short range relaxation. The presence of non-Debye type relaxation is revealed from Nyquist plots and enabled to separate the contribution from bulk and grain boundary effect in the material. Further, the ac electrical conductivity of the material was well agreed with the Jonscher's universal power law. (Source: Physics Letters A)Physics Letters AjournalsThu, 15 Aug 2019 11:12:27 +0100719072294Modified KdV equation for magnetized Rossby waves in a zonal flow of the ionospheric E-layer
https://medworm.com/719072293/modified-kdv-equation-for-magnetized-rossby-waves-in-a-zonal-flow-of-the-ionospheric-e-layer/
Publication date: Available online 14 August 2019Source: Physics Letters AAuthor(s): T. Kaladze, L. Tsamalashvili, D. Kaladze, O. Özcan, A. Yesil, M. IncAbstractNonlinear interaction of magnetized Rossby waves with sheared zonal flow in the Earth's ionospheric E-layer is investigated. It is shown that in case of weak nonlinearity 2D Charney vorticity equation can be reduced to the one-dimensional modified KdV equation. (Source: Physics Letters A)Physics Letters AjournalsThu, 15 Aug 2019 11:12:27 +0100719072293Effect of magnetic field on a multi window ladder type electromagnetically induced transparency with 87Rb atoms in vapour cell
https://medworm.com/718913657/effect-of-magnetic-field-on-a-multi-window-ladder-type-electromagnetically-induced-transparency-with/
We report the observation of nine such windows. Such multi window EIT systems are capable of storing pulses at the different frequencies, corresponding to these windows hence paving the way for realization of multi frequency quantum memories. Also, the total bandwidth of storage is 218.4 MHz which is two orders of magnitude higher than that typically obtained in single window EIT based storage systems. These systems have tremendous applications in the field of speedy transmission of data over a long distance quantum communication channel. (Source: Physics Letters A)Physics Letters AjournalsWed, 14 Aug 2019 21:12:22 +0100718913657Influence of the long-range forces in non-Gaussian random-packing dynamics
https://medworm.com/718913656/influence-of-the-long-range-forces-in-non-gaussian-random-packing-dynamics/
Publication date: Available online 13 August 2019Source: Physics Letters AAuthor(s): Carlos Handrey Araujo FerrazAbstractIn this paper, we perform molecular dynamics (MD) simulations to study the random packing of spheres with different particle size distributions. In particular, we deal with non-Gaussian distributions by means of the Lévy distributions. The initial positions as well as the radii of five thousand non-overlapping particles are assigned inside a confining rectangular box. After that, the system is allowed to settle under gravity towards the bottom of the box. Both the translational and rotational movements of each particle are considered in the simulations. In order to deal with interacting particles, we take into account both the contact and long-range cohesive forces. The...Physics Letters AjournalsWed, 14 Aug 2019 21:12:22 +0100718913656Magnon spin Nernst effect on the antiferromagnetic checkerboard lattice
https://medworm.com/718913655/magnon-spin-nernst-effect-on-the-antiferromagnetic-checkerboard-lattice/
Publication date: Available online 13 August 2019Source: Physics Letters AAuthor(s): A.S.T. PiresAbstractIn this paper we study topological effects in an anisotropic checkerboard antiferromagnetic lattice in the presence of the Dzyaloshinskii- Moriya interaction (DMI). The time reversal symmetry is broken by anisotropies in the Hamiltonian. However, in contrast to the honeycomb lattice, the DMI does not open a gap here. We calculate the energy spectrum of the magnons and the spin Nernst coefficient in the presence of a longitudinal temperature gradient. (Source: Physics Letters A)Physics Letters AjournalsWed, 14 Aug 2019 21:12:22 +0100718913655Evolution processes of coupled thermal qubits
https://medworm.com/717816915/evolution-processes-of-coupled-thermal-qubits/
Publication date: Available online 9 August 2019Source: Physics Letters AAuthor(s): Theerawat Chatchawaltheerat, Supitch Khemmani, Julian PoulterAbstractWe investigate the quantum speed limit time (QSLT) of quantum evolution before thermal equilibrium of two coupled qubits each of which is coupled to a separate thermal bath at the same temperature within the Born-Markov approximation. The evolution process in one particular initial state can change between speed-up and speed-down two times before reaching equilibrium. We call this double cusp behaviour. This behaviour is an anomalous phenomenon in evolution processes in the weak-coupling Markovian regime. We study QSLT corresponding to all pure initial energy eigenstates and categorise them. In addition, we also display the conditions for ...Physics Letters AjournalsSat, 10 Aug 2019 18:12:24 +0100717816915First-principles study of metal-semiconductor contact between MX2 (M = Nb, Pt; X = S, Se) monolayers
https://medworm.com/717816914/first-principles-study-of-metal-semiconductor-contact-between-mx2-mnb-pt-xs-se-mo/
Publication date: Available online 9 August 2019Source: Physics Letters AAuthor(s): Akmal Khan, H.U. Din, M. Idrees, Fawad Khan, Tahani A. Alrebdi, Chuong V. Nguyen, M. Shafiq, B. AminAbstractFirst principles calculations are performed to investigate the structural and electronic properties of MX2 (M = Nb, Pt; X = S, Se) monolayers and their van der Waals (vdW) heterostructures. The dynamical stability of monolayers and vdW heterostructures is confirmed by binding energy and phonon spectra. An indirect band gap nature is found for PtS2 and PtSe2 monolayers while NbS2, NbSe2 and all vdW heterostructures are metals. The intrinsic electronic properties of both NbX2 and PtX2 are well preserved due to weak vdW contact. It is demonstrated that a p-type Schottky contact with a small barri...Physics Letters AjournalsSat, 10 Aug 2019 18:12:24 +0100717816914Determining local inhomogeneities of rotating plasma density via microwave refraction
https://medworm.com/717504498/determining-local-inhomogeneities-of-rotating-plasma-density-via-microwave-refraction/
Publication date: Available online 8 August 2019Source: Physics Letters AAuthor(s): Yu.V. Kovtun, Y.V. SiuskoAbstractA method for determining local inhomogeneities of the rotating plasmas is proposed. This method is based on spectral and correlation analysis of the reflected signals from the plasma at normal and oblique microwave incidence. Experimental approbation of the method is made. (Source: Physics Letters A)Physics Letters AjournalsFri, 09 Aug 2019 14:12:26 +0100717504498Induction of an atomically thin ferromagnetic semiconductor in 1T′ phase ReS2 by doping with transition metals
https://medworm.com/717504497/induction-of-an-atomically-thin-ferromagnetic-semiconductor-in-1t-phase-res2-by-doping-with-trans/
Publication date: Available online 8 August 2019Source: Physics Letters AAuthor(s): Jing Pan, Xiaoyu Zhou, Jiansheng Zhong, Jingguo HuAbstractTwo-dimensional 1T′ phase ReS2, a transition metal dichalcogenide, has a unique structure and electronic properties that are independent of thickness. The pure phase is a nonmagnetic semiconductor. Using density functional theory calculations, we show that ReS2 can be tuned to a magnetic semiconductor by doping with transition metal atoms. The magnetism mainly comes from the dopant transition metal and neighboring Re and S atoms as a result of competition between exchange splitting and crystal field splitting. ReS2 doped with Co can be considered as a promising diluted magnetic semiconductor owing to its strong ferromagnetism with long-range ferrom...Physics Letters AjournalsFri, 09 Aug 2019 14:12:26 +0100717504497Power threshold and confinement in discharges achieving high-βN H-mode phases on EAST tokamak
https://medworm.com/717504496/power-threshold-and-confinement-in-discharges-achieving-high-n-h-mode-phases-on-east-tokamak/
Publication date: Available online 8 August 2019Source: Physics Letters AAuthor(s): Yanjun Liu, Zixi Liu, Xiang Gao, Tao Zhang, Yao Yang, Hong Li, Jinlin Xie, Adi Liu, Tao Lan, Chu Zhou, Wenzhe Mao, Weixing Ding, Ge Zhuang, Wandong Liu, EAST TeamAbstractA series of discharges achieving high-βN(>1.5) H-mode phases were obtained on EAST with both LHW and NBI as the heating power, a tungsten divertor, an unfavorable ▽B×B direction configuration for the L-H transition and a lower toroidal field (BT∼1.6T). The experimental power threshold with the unfavorable direction configuration appeared to be higher than previous results with favorable directions in 2014 and 2015, although the tungsten divertor configurations were believed to benefit the L-H transition compared to a graphite divertor...Physics Letters AjournalsFri, 09 Aug 2019 14:12:26 +0100717504496Resonant light absorption and plasmon tunability of lateral triangular Au nanoprisms array
https://medworm.com/717504495/resonant-light-absorption-and-plasmon-tunability-of-lateral-triangular-au-nanoprisms-array/
Publication date: Available online 8 August 2019Source: Physics Letters AAuthor(s): Mengyao Gao, Xuanli Zheng, Imran Khan, Haoyuan Cai, Jinshen Lan, Jing Liu, Jiayuan Wang, Jianyang Wu, Shengli Huang, Shuping Li, Junyong KangAbstractOptical characteristics and electric field distribution of triangular Au nanoprism in a unit and units array under polarized light irradiation were systematically studied by numerical simulation with finite difference time domain method. It is found that the plasmonic properties of the triangular nanoprism are dominated by the electric polarization rather than the wave propagation. The triangular nanoprism presents similar optical response with a strong dipole band under different wave propagations if the electric polarization vectors are parallel to the triang...Physics Letters AjournalsFri, 09 Aug 2019 14:12:26 +0100717504495Electronic properties of the Dirac and Weyl systems with first- and higher-order dispersion in non-Fermi-liquid picture
https://medworm.com/717347539/electronic-properties-of-the-dirac-and-weyl-systems-with-first-and-higher-order-dispersion-in-non-f/
Publication date: Available online 7 August 2019Source: Physics Letters AAuthor(s): Chen-Huan WuAbstractWe investigate the non-Fermi-liquid behaviors of the 2D and 3D Dirac/Weyl systems with low-order and higher order dispersion. The self-energy correction, symmetry, free energy, optical conductivity, density of states, and spectral function are studied. We found that, for Dirac/Weyl systems with higher order dispersion, the non-Fermi-liquid features remain even at finite chemical potential, and they are distinct from the ones in Fermi-liquid picture and the conventional non-Fermi-liquid picture. The power law dependence of the physical observables on the energy as well as the logarithmic renormalizations due to the long-range Coulomb interaction are showed. The Landau damping of the longi...Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347539Peculiarities of melting and crystallization of n-decane in a porous glass
https://medworm.com/717347538/peculiarities-of-melting-and-crystallization-of-n-decane-in-a-porous-glass/
Publication date: Available online 7 August 2019Source: Physics Letters AAuthor(s): A.L. Pirozerski, O.I. Smirnova, A.I. Nedbai, O.L. Pirozerskaya, N.A. Grunina, V.M. MikushevAbstractMelting and crystallization of n-decane embedded into porous glass with the mean pore size of about 6.4 nm were studied using acoustic and DSC methods. Smearing of the phase transitions, decrease of melting and freezing temperatures, pronounced hysteresis between melting and crystallization were revealed by both methods. In DSC measurements for the pore filling factors 70% and higher double peaks were observed upon cooling while only single peaks were present upon heating. Also a high reduction of the corresponding phase transition heats was revealed. Melting and freezing intervals determined by acoustic and D...Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347538Microstructure and magnetic properties of NdFeB alloys by co-doping alnico elements
https://medworm.com/717347537/microstructure-and-magnetic-properties-of-ndfeb-alloys-by-co-doping-alnico-elements/
Publication date: Available online 7 August 2019Source: Physics Letters AAuthor(s): Sajjad Ur Rehman, Qingzheng Jiang, Lunke He, Houdong Xiong, Kai Liu, Lei Wang, Munan Yang, Zhenchen ZhongAbstractElements of alnico 8 are added into Nd-Fe-B alloys fabricated by rapid solidification method. It is observed that the magnetic properties at high temperature improved by small addition of alnico elements. The Curie temperature of the alloys increased from 580 K for standard alloy to 639 K by 20 % addition of alnico 8 elements. The spin reorientation temperature decreased from 133 K to 104 K. The TEM analysis showed that elements of alnico 8 refine the microstructure of Nd-Fe-B ribbons. The STEM analysis confirmed the heterogeneous distribution of Nd, Fe, Cu, Al, Ni and homogeneous distribution of...Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347537Deconvolution of 3-D Gaussian kernels
https://medworm.com/717347536/deconvolution-of-3-d-gaussian-kernels/
Publication date: Available online 7 August 2019Source: Physics Letters AAuthor(s): Z.K. SilagadzeAbstractUlmer and Kaissl formulas for the deconvolution of one-dimensional Gaussian kernels are generalized to the three-dimensional case. The generalization is based on the use of the scalar version of the Grad's multivariate Hermite polynomials which can be expressed through ordinary Hermite polynomials. (Source: Physics Letters A)Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347536Understanding the conduction and switching mechanism of Ti/AlOx/TaOx/Pt analog memristor
https://medworm.com/717347535/understanding-the-conduction-and-switching-mechanism-of-tialoxtaoxpt-analog-memristor/
Publication date: Available online 7 August 2019Source: Physics Letters AAuthor(s): Sen Liu, Yi Sun, Bing Song, Zhiwei Li, Haijun Liu, Qingjiang LiAbstractIn this letter, the conduction and bipolar switching mechanism of the ultrathin AlOx(3 nm)/TaOx(5 nm) memristor are investigated through the electrical characterization and elemental analysis. The AlOx/TaOx memristor exhibits high uniformity and excellent analog property after initial reset process. The following experiments and analyses demonstrate that the switching behavior could take place over the whole area of TaOx/Pt interface and is dominated by the tunneling barrier modulation induced by oxygen ions migration. (Source: Physics Letters A)Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347535Estimation of decoherence in electromechanical circuits
https://medworm.com/717347534/estimation-of-decoherence-in-electromechanical-circuits/
Publication date: Available online 7 August 2019Source: Physics Letters AAuthor(s): Olímpio P. de Sá Neto, Helder A.S. CostaAbstractThis letter presents a schematic circuit with capacitive coupling between the CPW Cavity Center Trace (resonated with electromagnetic mode) and the mechanical Nanoresonator mediated by Transmon, resulting in the Cross-Kerr electromechanical effect. Then we show the dynamics of quantum states, showing the generation of superposition states and bipartite entanglement of continuous variables through nonlinear quantum electrodynamics in the circuit. Finally, we calculated and estimated the parameter for mechanical outcome through phase measurements of the CPW Cavity Center Trace electromagnetic mode. (Source: Physics Letters A)Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347534The mechanical flexibility, electronic structure and carrier mobility of monolayer GeP: A first principles study
https://medworm.com/717347533/the-mechanical-flexibility-electronic-structure-and-carrier-mobility-of-monolayer-gep-a-first-prin/
Publication date: Available online 7 August 2019Source: Physics Letters AAuthor(s): Jie Sun, Jiancai LengAbstractInspired by successful exfoliation in experiment, we explore mechanical, electronic and transport properties of GeP monolayer using first-principles calculations. It is found that the cleavage energy of GeP monolayer is ∼0.39 J/m2, verifying it can be feasibly extracted from its bulk form. The calculated stress-strain relation reveals that monolayer GeP can withstand a tensile stress and strain up to 14.88 GPa and 28%, respectively. The band structure calculations indicate the monolayer GeP possesses an indirect band gap ∼2.28 eV, which can be reduced to 0.43 eV and experiences an indirect-direct transition when axial strain is applied. Besides, the effective masses can be d...Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347533Some remarks on dual helicity flag-dipole spinors
https://medworm.com/717347532/some-remarks-on-dual-helicity-flag-dipole-spinors/
In this report we advance into a mapping procedure transmuting a single helicity spinor into a dual helicity spinor. Such a mathematical mechanism reveal us a class of spinor which fits into fourth class within Lounesto classification [1]. The focus of the present manuscript is to expose the algebraic construction of flag-dipole spinors and briefly explore its underlying physical and mathematical contents. (Source: Physics Letters A)Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347532Editors
https://medworm.com/717347492/editors/
Publication date: 2 September 2019Source: Physics Letters A, Volume 383, Issue 25Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 09 Aug 2019 00:09:30 +0100717347492Group chase and escape with prey's anti-attack behavior
https://medworm.com/717033635/group-chase-and-escape-with-preys-anti-attack-behavior/
Publication date: Available online 6 August 2019Source: Physics Letters AAuthor(s): Shuai Zhang, Mingyong Liu, Xiaokang Lei, Panpan Yang, Yunke Huang, Ruaridh ClarkAbstractGroup chase and escape is widely observed in nature, where the predators approach the prey and the prey try to escape. An interesting phenomenon occurs when a prey group is under attack, whereby some individuals perform anti-attack behavior that places themselves at a greater risks of being caught. It remains unclear why certain prey would risk their survival and what conditions and internal mechanisms trigger this anti-attack response. Using a set of local interaction rules among prey and predators, we proposed a continuous-space and discrete-time model that incorporates energy level, variable speed and handling time by...Physics Letters AjournalsWed, 07 Aug 2019 20:03:27 +0100717033635A first-principles insight into Pd-doped MoSe2 monolayer: A toxic gas scavenger
https://medworm.com/717033634/a-first-principles-insight-into-pd-doped-mose2-monolayer-a-toxic-gas-scavenger/
Publication date: Available online 6 August 2019Source: Physics Letters AAuthor(s): Shouxiao Ma, Liancun Su, Li Jin, Jinsheng Su, Ying JinAbstractUsing first-principles theory, we investigate the Pd-doping effect on the geometric and electronic behaviors of MoSe2 monolayer, and the adsorption behavior of Pd-MoSe2 monolayer upon four toxic gases, namely NO, NO2 SO2 and H2S. Desorption property of Pd-MoSe2 monolayer upon four gases at diverse temperatures is analyzed as well to help explore its potential application. For Pd dopant adsorption onto MoSe2 monolayer, somewhat n-type doping is determined, which accounts for the increased conductivity for intrinsic MoSe2 monolayer. The strong adsorption ability and poor desorption performance of Pd-MoSe2 monolayer upon four gases indicate its larg...Physics Letters AjournalsWed, 07 Aug 2019 20:03:27 +0100717033634A time-series approach to measuring node similarity in networks and its application to community detection
https://medworm.com/717033633/a-time-series-approach-to-measuring-node-similarity-in-networks-and-its-application-to-community-det/
Publication date: Available online 6 August 2019Source: Physics Letters AAuthor(s): Bo Yang, Tao Huang, Xu LiAbstractA central concept in network analysis is that of similarity between nodes. In this paper, we introduce a dynamic time-series approach to quantifying the similarity between nodes in networks. The problem of measuring node similarity is exquisitely embedded into the framework of time series for state evolution of nodes. We develop a deterministic parameter-free diffusion model to drive the dynamic evolution of node states, and produce a unique time series for each source node. Then we introduce a measure quantifying how far all the other nodes are located from each source one. Following this measure, a quantity called dissimilarity index is proposed to signify the extent of si...Physics Letters AjournalsWed, 07 Aug 2019 20:03:27 +0100717033633Magnetic quantum ring in two-dimensional topological insulators
https://medworm.com/716718835/magnetic-quantum-ring-in-two-dimensional-topological-insulators/
Publication date: Available online 5 August 2019Source: Physics Letters AAuthor(s): Guo Li, Ning Yang, Weidong Chu, Haifeng Song, Jia-Lin ZhuAbstractThe quantum properties of topological insulator magnetic quantum rings formed by inhomogeneous magnetic fields are investigated using a series expansion method for the modified Dirac equation. Cycloid-like and snake-like magnetic edge states are respectively found in the bulk gap for the normal and inverted magnetic field profiles. The energy spectra, current densities and classical trajectories of the magnetic edge states are discussed in detail. The bulk band inversion is found to manifest itself through the angular momentum transition in the ground state for the cycloid-like states and the resonance tunneling effect for the snake-like state...Physics Letters AjournalsTue, 06 Aug 2019 15:15:26 +0100716718835Tuning the electronic and magnetic properties of zigzag silicene nanoribbons by 585 defects
https://medworm.com/716718834/tuning-the-electronic-and-magnetic-properties-of-zigzag-silicene-nanoribbons-by-585-defects/
Publication date: Available online 5 August 2019Source: Physics Letters AAuthor(s): Haixia Dong, Dangqi Fang, Baihua Gong, Yang Zhang, Erhu Zhang, Shengli ZhangAbstractUsing first-principles calculations, we study the geometric structures, formation energies, electronic and magnetic properties of zigzag silicene nanoribbons (ZSiNRs) with 585 defects. There are two kinds of 585 defects in ZSiNRs referred as 585-Iand 585-II, respectively. It is found that no matter which one of the two types, it is the most stable at the edge of the ZSiNR, and at this time it is even more stable than that in an infinite silicene sheet. Utilizing 585 defects, it can transform ZSiNRs from antiferromagnetic semiconductors into metals or half-metals. Especially, defective ZSiNRs may display nearly 100% spin-pola...Physics Letters AjournalsTue, 06 Aug 2019 15:15:26 +0100716718834Surface electromagnetic waves at the interface between dissipative porous nanocomposite and hypercrystal under different temperatures
https://medworm.com/716718833/surface-electromagnetic-waves-at-the-interface-between-dissipative-porous-nanocomposite-and-hypercry/
Publication date: Available online 5 August 2019Source: Physics Letters AAuthor(s): I. FedorinAbstractIn the current paper the properties of surface plasmon polaritons as well as hybrid polarized surface electromagnetic waves at the plane interface of a porous semiconductor nanomaterial and a hypercrystal are studied theoretically and numerically. The nanomaterial, as well as the hypercrystal, is made of n-type doped indium antimonide (n-InSb) semiconductor layers. The losses which inherent to the semiconductor materials are taken into account. To describe the properties of the constituent semiconductor layers the approximate analytical temperature models for concentration and mobility of conduction electrons are applied. This allows to consider the effect of electron scattering on the pro...Physics Letters AjournalsTue, 06 Aug 2019 15:15:26 +0100716718833Thermoelectric performance of monolayer Bi2Te2Se of ultra low lattice thermal conductivity
https://medworm.com/716718832/thermoelectric-performance-of-monolayer-bi2te2se-of-ultra-low-lattice-thermal-conductivity/
Publication date: Available online 5 August 2019Source: Physics Letters AAuthor(s): Bin Xu, Liangong Song, Gaohui Peng, Jing Zhang, Shanshan Ma, Yusheng Wang, Yuanxu WangAbstractThe electronic structure and thermoelectric properties of monolayer Bi2Te2Se were studied by density functional theory and semi-classical Boltzmann transport equation. The band gap with TB-mBJ can be improved for monolayer Bi2Te2Se. Monolayer Bi2Te2Se have ultra-low thermal conductivity comparing with other well-known two-dimensional materials. The monolayer Bi2Te2Se can improve electrical conductivities. ZT increases with increasing temperature for monolayer Bi2Te2Se. Comparing to GGA, TB-mBJ has larger ZT value in p-type doping. Monolayer Bi2Te2Se have larger ZT comparing with other well-known two-dimensional mat...Physics Letters AjournalsTue, 06 Aug 2019 15:15:26 +0100716718832Phase transition of a second kind in nickel as observed through optical reflection under pressure
https://medworm.com/716718831/phase-transition-of-a-second-kind-in-nickel-as-observed-through-optical-reflection-under-pressure/
Publication date: Available online 5 August 2019Source: Physics Letters AAuthor(s): Moris Sudai, Noaz Nissim, Shalom EliezerAbstractThe magnetic permeability of materials at optical frequencies is usually suggested in the literature to be μ=1. In this case one cannot expect to measure the magnetic second order phase transition at optical frequencies. The main novel idea of this paper is that the magnetic permeability μ is not equal to 1 for optical frequency and a phase transition of magnetism was measured experimentally with an optical frequency. In particular, this work presents the detection of a magnetic second order phase transition in nickel with temperature and at different pressures, by reflectivity measurements at an optical frequency. Based on our experiments the magnetic perme...Physics Letters AjournalsTue, 06 Aug 2019 15:15:26 +0100716718831Orthorhombic C10: A new superdense carbon allotrope
https://medworm.com/715939468/orthorhombic-c10-a-new-superdense-carbon-allotrope/
Publication date: Available online 2 August 2019Source: Physics Letters AAuthor(s): Qun Wei, Wen Tong, Ruike Yang, Haiyan Yan, Bing Wei, Meiguang Zhang, Xinchao Yang, Rui ZhangAbstractBy using unbiased crystal structure searching technique combined with first-principles calculations, a new superdense carbon phase C10 (space group: C222) with a density of 3.55g/cm3 (larger than that of diamond (3.50g/cm3)) is uncovered. The C10 phase has a 10-atom unit cell in the full sp3 bonding network. A systematic theoretical study of the electronic, dynamic, optical, and elastic properties of superdense carbon C10 was carried out. In addition, we studied the homologous fracture mode by calculating the ideal tensile and shear strength of C10 phase. It was confirmed that C10 is a superhard insulator mat...Physics Letters AjournalsSat, 03 Aug 2019 16:42:26 +0100715939468Nitrogen-rich GaN5 and GaN6 as High Energy Density Materials With Modest Synthesis Condition
https://medworm.com/715939467/nitrogen-rich-gan5-and-gan6-as-high-energy-density-materials-with-modest-synthesis-condition/
Publication date: Available online 2 August 2019Source: Physics Letters AAuthor(s): Zhao Liu, Da Li, Shuli Wei, Yan Liu, Fubo Tian, Defang Duan, Tian CuiAbstractHere, the energetic gallium nitrides with the network and zigzag poly-nitrogen configurations at modest pressures have been predicted. The nitrogen-rich Cmc21-GaN5, high-pressure P21/m-GaN5 and C2/c-GaN6 phases can release higher energy of ∼3.27 kJ g−1, 4.12 kJ g−1, 5.71 kJ g−1, respectively, which are close to or even higher than that of the traditional high energy density materials TNT and possess distinguished detonation performance simulated. The predicted synthesis pressures of GaN5 and GaN6 (25 and 50 GPa) are much lower than that of the famous atomic cg-N. The VSEPR theory and Zintl-Klemm concept are employed to reas...Physics Letters AjournalsSat, 03 Aug 2019 16:42:26 +0100715939467LiB6Si: An indirect band gap semiconductor
https://medworm.com/715939466/lib6si-an-indirect-band-gap-semiconductor/
Publication date: Available online 2 August 2019Source: Physics Letters AAuthor(s): Zhikang Yuan, Dongli YuAbstractUsing first-principle calculations, mechanical properties, electronic structure, and Raman spectra of LiB6Si structure were investigated. The band structures calculated by GGA-PBE and HSE06 methods reveal that LiB6Si is an indirect band gap semiconductor. The band gap estimated by HSE06 method is about 2.24 eV, which is in good agreement with that of experimental value 2.27 eV. The calculated tensile stress-strain curves of LiB6Si reveal that [010] direction is the cleavage direction under tensile strains. The calculated Raman spectra of LiB6Si are also in good agreement with that of measured. The position of the band gap may provide a basis for further photocatalysis research...Physics Letters AjournalsSat, 03 Aug 2019 16:42:26 +0100715939466Investigate the z-average mean-square radius of gyration of star-shape polymers using the average number of subchains
https://medworm.com/715939465/investigate-the-z-average-mean-square-radius-of-gyration-of-star-shape-polymers-using-the-average-nu/
Publication date: Available online 2 August 2019Source: Physics Letters AAuthor(s): Yuelan Tian, Hongzan Song, Fang Gu, Libin Bai, Haijun Wang, Xinwu BaAbstractThe general treatment is proposed to investigate the explicit expressions of the average number of subchains with definite monomer sequences on the polymer skeleton, in which the AB+Af type polycondensation is chosen as the classical model of polymerization. The linear homo-polymers and star-shape co-polymers are examined to derive the z-average mean-square radius of gyration, respectively, where the mass of monomers are taken into consideration. Furthermore, the z-average mean-square radius of gyration of mixture sample is calculated, in which the weight factors of the co-polymer and homo-polymer for the non-fractionated samples ar...Physics Letters AjournalsSat, 03 Aug 2019 16:42:26 +0100715939465Perspectives on spin hydrodynamics in ferromagnetic materials
https://medworm.com/715939464/perspectives-on-spin-hydrodynamics-in-ferromagnetic-materials/
This article provides an overview of the theoretical foundations of spin hydrodynamics and their physical interpretation in the context of spin transport. We discuss other proposed applications for spin hydrodynamics as well as our view on challenges and future research directions. (Source: Physics Letters A)Physics Letters AjournalsSat, 03 Aug 2019 16:42:26 +0100715939464Efficiency and power enhancement of solar cells by dark states
https://medworm.com/715939463/efficiency-and-power-enhancement-of-solar-cells-by-dark-states/
Publication date: Available online 2 August 2019Source: Physics Letters AAuthor(s): Sangchul OhAbstractWe study how dark states enhance the efficiency and power of a solar cell as a quantum heat engine. Conventional approaches assume the solar cell is in thermal equilibrium with both hot and cold baths simultaneously. We propose an description that a solar cell is surrounded only by the cold bath and the thermal radiation from the hot bath is described by a pumping term in a master equation. We calculated the current-voltage curve, the power-voltage curve, the efficiency, and the power of the solar cell for different photon fluxes. It is found that as the photon flux increases, the power output increases linearly at first and then becomes saturated, but the efficiency decreases rapidly. It...Physics Letters AjournalsSat, 03 Aug 2019 16:42:26 +0100715939463Beam-core evolution equation and space-charge limit
https://medworm.com/715474062/beam-core-evolution-equation-and-space-charge-limit/
Publication date: Available online 31 July 2019Source: Physics Letters AAuthor(s): Taufik, Ken TakayamaAbstractThe nonlinear beam-core evolution equation approach is proposed as a powerful tool to estimate the acceptable beam current in a given circular accelerator. The approach is justified by the macroparticle simulation over a wide beam current parameter region. Space-charge effects on the beam-core evolution are discussed by Poincaré mapping on the beam-core phase space (σ, dσ/ds). The instability seen in the beam-core evolution is rigorously analyzed as an eigenvalue problem in the coupled linear system derived from the linearized beam-core evolution equations. A threshold current resulting in the instability is given by both the nonlinear beam-core evolution equation approach and ...Physics Letters AjournalsThu, 01 Aug 2019 22:36:38 +0100715474062On the thermophoresis in dense dust structures in neon plasma
https://medworm.com/715161356/on-the-thermophoresis-in-dense-dust-structures-in-neon-plasma/
Publication date: Available online 30 July 2019Source: Physics Letters AAuthor(s): V.V. Shumova, D.N. Polyakov, E.K. Mataybaeva, L.M. VasilyakAbstractNumerical study of the effect of dust particle concentration on the thermophoretic force acting on a dust particle inside a dust structure in plasma has been carried out. The experimental data on the formation of voids in dust structures formed by 2.55 μm dust particles in a glow dc discharge in neon have been used. The simulation has been performed using the diffusion-drift model with taking into account joule heating of discharge. The dependence of the thermophoretic force acting on a dust particle in a dust structure on the ratio of atom mean free path to the distance between the adjacent particles in the dust structure has been obtained....Physics Letters AjournalsWed, 31 Jul 2019 18:03:31 +0100715161356Quantifying information loss on chaotic attractors through recurrence networks
https://medworm.com/715161355/quantifying-information-loss-on-chaotic-attractors-through-recurrence-networks/
Publication date: Available online 30 July 2019Source: Physics Letters AAuthor(s): K.P. Harikrishnan, R. Misra, G. AmbikaAbstractWe propose an entropy measure for the analysis of chaotic attractors through recurrence networks which are un-weighted and un-directed complex networks constructed from time series of dynamical systems using specific criteria. We show that the proposed measure converges to a constant value with increase in the number of data points on the attractor (or the number of nodes on the network) and the embedding dimension used for the construction of the network, and clearly distinguishes between the recurrence network from chaotic time series and white noise. Since the measure is characteristic to the network topology, it can be used to quantify the information loss as...Physics Letters AjournalsWed, 31 Jul 2019 18:03:31 +0100715161355Editors
https://medworm.com/714850026/editors/
Publication date: 22 August 2019Source: Physics Letters A, Volume 383, Issue 24Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 30 Jul 2019 13:13:19 +0100714850026Shape-induced anisotropy in epitaxial Fe3O4 nanopillars
https://medworm.com/713613497/shape-induced-anisotropy-in-epitaxial-fe3o4-nanopillars/
Publication date: Available online 24 July 2019Source: Physics Letters AAuthor(s): M. Guan, G. Dong, Z. Hu, B. Peng, Y. He, W.Z. Cui, Z. Zhou, M. LiuAbstractFe3O4 nanopillars with remarkably high uniformity and crystallinity are grown on (100)-oriented magnesium aluminate substrates by pulsed laser deposition with a simple anodic-aluminum-oxide template method. Compared with Fe3O4 full film, the nanopillars exhibit higher in-plane magnetic saturation field and lower out-of-plane saturation field. The angular-dependent ferromagnetic resonance, investigated by electron spin resonance spectroscopy, confirms the shape-induced anisotropy change in Fe3O4 nanopillars. High Gilbert damping parameter of 0.23 is obtained by measuring the resonance field at different microwave frequencies. (Source: P...Physics Letters AjournalsThu, 25 Jul 2019 20:03:33 +0100713613497Magnetotransport in a zigzag monolayer MoS2 nanoribbon with ferromagnetic electrodes
https://medworm.com/713613496/magnetotransport-in-a-zigzag-monolayer-mos2-nanoribbon-with-ferromagnetic-electrodes/
Publication date: Available online 24 July 2019Source: Physics Letters AAuthor(s): J.-J. Jin, R.-Y. Yuan, Q.-J. Yang, J.L. Tang, A.G. Du, J. Zheng, Y. GuoAbstractIn this research, using the three-band tight-binding model combined with a non-equilibrium Green's function technique, spin-dependent electron transport was investigated in the quantum structure of zigzag monolayer molybdenum disulfide with ferromagnetic electrodes. It was shown that in parallel configurations, the conductance exhibited a quantized oscillating phenomenon, while in the antiparallel configurations with increasing magnetization, the conductance showed a zero platform in a large-energy region. We observed a giant magnetoresistance effect. Moreover, the length of the central part of the structure had a certain influenc...Physics Letters AjournalsThu, 25 Jul 2019 20:03:33 +0100713613496Spin-independent and spin-dependent re-excitation in CdZnTe studied by pump-probe spectroscopy
https://medworm.com/713613495/spin-independent-and-spin-dependent-re-excitation-in-cdznte-studied-by-pump-probe-spectroscopy/
Publication date: Available online 24 July 2019Source: Physics Letters AAuthor(s): Lihua Teng, Lijun Mu, Xia WangAbstractTime-resolved pump-probe spectroscopy is used to study the re-excitation processes of spin-balanced and spin-polarized electrons trapped by the defect levels in Cd0.86Zn0.14Te. In CdTe, Cd0.96Zn0.04Te, and Cd0.86Zn0.14Te, the electron trapping time and lifetime decrease with the increasing defect density of states that depends on the Zn composition. The abnormal linearly and circularly polarized pump-probe spectroscopies, respectively, demonstrate the presence of spin-independent and spin-dependent re-excitation processes in Cd0.86Zn0.14Te which have high defect density of states. (Source: Physics Letters A)Physics Letters AjournalsThu, 25 Jul 2019 20:03:33 +0100713613495Generalized Ablowitz-Ladik equation with a dual Lagrangian structure
https://medworm.com/713301307/generalized-ablowitz-ladik-equation-with-a-dual-lagrangian-structure/
This article presents a generalized Ablowitz-Ladik (GAL) equation that can be obtained by means of the least action principle in two different ways. This GAL equation may describe the evolution of a discrete system, in which case it is derived from a Langrangian L which obeys a standard Lagrange equation. But this GAL equation may also describe a continuous system with nonlocal interactions, and in this case it is obtained from a different Lagrangian density L which obeys completely different Euler-Lagrange equations. The Lagrangian density L permits us to obtain variational solutions and Noether's conservation laws. Anderson's variational method predicts the existence of breathers and soliton-like solutions, and direct numerical solutions confirm the existence of these waves. The relation...Physics Letters AjournalsWed, 24 Jul 2019 14:12:30 +0100713301307The influence of random edge defects on the electric and optical properties of phosphorene nanoribbons along zigzag direction
https://medworm.com/713144248/the-influence-of-random-edge-defects-on-the-electric-and-optical-properties-of-phosphorene-nanoribbo/
Publication date: Available online 22 July 2019Source: Physics Letters AAuthor(s): Zhe Zhou, Jian Li, Jie-Yun YanAbstractPhosphorene nanoribbons are one-dimensional semiconductors with possible edge states falling within its energy bandgap. We build the connection between the possible configurations of edge defects and the corresponding electric and optical properties in practice systems. The influence of the random defects or roughness at the edges of phosphorene nanoribbons cutting along zigzag direction is investigated quantitatively. Theoretical calculations show that the absorption peak due to the transitions involving edge states has an obvious blue shift with the zigzag-type positions at the edges increasing. The absorption thus can be used to estimate the random defects or roughnes...Physics Letters AjournalsWed, 24 Jul 2019 00:03:32 +0100713144248Principle of Unattainability of absolute zero temperature, the Third Law of Thermodynamics, and projective quantum measurements
https://medworm.com/713144247/principle-of-unattainability-of-absolute-zero-temperature-the-third-law-of-thermodynamics-and-proj/
Publication date: Available online 22 July 2019Source: Physics Letters AAuthor(s): Tien D. KieuAbstractThe Principle of Unattainability rules out the attainment of absolute zero temperature by any finite physical means, no matter how idealised they could be. Nevertheless, we clarify that the Third Law of Thermodynamics, as defined by Nernst's heat theorem statement, is distinct from the Principle of Unattainability in the sense that the Third Law is mathematically equivalent only to the unattainability of absolute zero temperature by quasi-static adiabatic processes. This, on the one hand, leaves open the possibility of attainability of absolute zero by non-adiabatic means, without violating the Third Law. On the other hand, we point out some apparent incompatibility between the Postulate ...Physics Letters AjournalsWed, 24 Jul 2019 00:03:32 +0100713144247A physical perspective on classical cloning
https://medworm.com/713144246/a-physical-perspective-on-classical-cloning/
Publication date: Available online 22 July 2019Source: Physics Letters AAuthor(s): Anirudh Reddy, Joseph Samuel, Supurna SinhaAbstractThe celebrated quantum no-cloning theorem states that an arbitrary quantum state cannot be cloned perfectly. This raises questions about cloning of classical states, which have also attracted attention. Here, we present a physical approach to the classical cloning process showing how cloning can be realised using Hamiltonians. After writing down a canonical transformation that clones classical states, we show how this can be implemented by Hamiltonian evolution. We then propose an experiment using the tools of nonlinear optics to realise the ideas presented here. Finally, to understand the cloning process in a more realistic context, we introduce statistical...Physics Letters AjournalsWed, 24 Jul 2019 00:03:32 +0100713144246Robust entanglement transfer through a disordered qubit ladder
https://medworm.com/713144245/robust-entanglement-transfer-through-a-disordered-qubit-ladder/
Publication date: Available online 22 July 2019Source: Physics Letters AAuthor(s): Guilherme M.A. Almeida, Andre M.C. Souza, Francisco A.B.F. de Moura, Marcelo L. LyraAbstractWe study an entanglement transfer protocol in a two-leg ladder spin-1/2 chain in the presence of disorder. In the scenario where the on-site energies and intrachain couplings are correlated, following approximately constant proportions along the chain, we set up a scheme for high-fidelity state transfer via a particular subspace wherein effective fluctuations in the parameters ultimately depend on the degree of such correlations, rather on the disorder featured by each leg individually, accounted by a box distribution of strength W. Moreover, we find that the leakage of information out of that subspace is suppressed u...Physics Letters AjournalsWed, 24 Jul 2019 00:03:32 +0100713144245Unambiguous determining the Curie point in perovskite manganite with second-order phase transition by scaling method
https://medworm.com/712366138/unambiguous-determining-the-curie-point-in-perovskite-manganite-with-second-order-phase-transition-b/
Publication date: Available online 19 July 2019Source: Physics Letters AAuthor(s): Yunfei Xie, Jiyu Fan, Lisha Xu, Xiyuan Zhang, Ruixing Xu, Yan Zhu, Rujun Tang, Caixia Wang, Chunlan Ma, Li Pi, Yuheng Zhang, Hao YangAbstractThe accurate determination of the Curie temperature (TC) is particularly important in describing the magnetic behavior close to the paramagnetic-ferromagnetic (PM-FM) phase transition. In this paper, we studied the magnetic phase transition and accurately predicted the Curie point of perovskite manganite La0.825Sr0.175MnO3. We find the compound shows a second-order PM-FM transition and has a large magnetic entropy change (MEC) in vicinity of phase transition region. Based on the scaling law and the correlation between magnetic field and MEC, the precise and magnetic-ind...Physics Letters AjournalsSun, 21 Jul 2019 01:12:28 +0100712366138High-pressure synthesis, structure and magnetic properties of LaCrO3 ceramics
https://medworm.com/712366137/high-pressure-synthesis-structure-and-magnetic-properties-of-lacro3-ceramics/
Publication date: Available online 19 July 2019Source: Physics Letters AAuthor(s): Hai-Shan Xu, Yan-Wei Yang, Rui-Long Wang, Hai-Bo Xiao, Ling-Fang Xu, Shi-Heng Liang, Chang-ping YangAbstractSingle-phase LaCrO3 ceramics was synthesized successfully by the solid state sintering method under high pressure (5 GPa). X-ray diffraction measurements suggest that the high-pressure synthesized sample is well-crystallized, but the cell volume is larger than that of the sample synthesized under ambient pressure, which can be ascribed to the occurrence of Cr2+ converted form part of Cr3+. Such mixed valent state with coexistence of Cr2+ and Cr3+ could be confirmed by X-ray photoelectron spectroscopy measurements. Magnetic measurement results indicate that in addition to antiferromagnetic superexchange...Physics Letters AjournalsSun, 21 Jul 2019 01:12:28 +0100712366137Ising model with invisible states on scale-free networks
https://medworm.com/712366136/ising-model-with-invisible-states-on-scale-free-networks/
Publication date: Available online 19 July 2019Source: Physics Letters AAuthor(s): Petro Sarkanych, Mariana KrasnytskaAbstractWe consider the Ising model with invisible states on scale-free networks. Our goal is to investigate the interplay between the entropic and topological influence on a phase transition. The former is manifest through the number of invisible states r, while the latter is controlled by the network node-degree distribution decay exponent λ. We show that the phase diagram, in this case, is characterised by two marginal values rc1(λ) and rc2(λ), which separate regions with different critical behaviours. Below the rc1(λ) line the system undergoes only second order phase transition; above the rc2(λ) – only a first order phase transition occurs; and in-between the lin...Physics Letters AjournalsSun, 21 Jul 2019 01:12:28 +0100712366136Spin thermoelectrics
https://medworm.com/712056356/spin-thermoelectrics/
Publication date: Available online 18 July 2019Source: Physics Letters AAuthor(s): Haiming Yu, Weiwei Lin, Jean-Philippe Ansermet (Source: Physics Letters A)Physics Letters AjournalsFri, 19 Jul 2019 21:06:29 +0100712056356Nonlinear excitation and stability analysis of ion-acoustic waves in a magnetized quantum plasma with exchange-correlation effects of degenerate electrons
https://medworm.com/712056355/nonlinear-excitation-and-stability-analysis-of-ion-acoustic-waves-in-a-magnetized-quantum-plasma-wit/
Publication date: Available online 18 July 2019Source: Physics Letters AAuthor(s): Shahzad Mahmood, Hafeez Ur-Rehman, Sajjad Hussain, Muhammad AdnanAbstractThe nonlinear ion-acoustic wave excitation and its stability analysis are investigated in a magnetized quantum plasma with exchange-correlation and Bohm diffraction effects of degenerate electrons in the model. Using reductive perturbation technique, the Zakharov-Kuznetsov (ZK) equation is derived for two dimensional propagation of ion-acoustic wave in a magnetized quantum plasma. It is found that the phase speed, amplitude and width of the nonlinear ion-acoustic wave structures are affected in the presence of exchange-correlation potential in the model. The stability analysis of the 2D ion-acoustic wave pulse is also presented. It is f...Physics Letters AjournalsFri, 19 Jul 2019 21:06:29 +0100712056355Structure transition and photoluminescence of CdS/Si nanoheterostructure array on thermal annealing
https://medworm.com/712056354/structure-transition-and-photoluminescence-of-cdssi-nanoheterostructure-array-on-thermal-annealing/
Publication date: Available online 18 July 2019Source: Physics Letters AAuthor(s): Peng Fei Ji, Yong Li, Yue Li Song, Feng Qun Zhou, Ming Li Tian, Shu Qing YuanAbstractCdS/Si heterojunctions have been prepared through growing CdS nanocrystallites (nc-CdS) on the silicon nanoporous pillar array (Si-NPA) by the chemical bath deposition method. Cadmium nanocrystallites (nc-Cd) have been observed and ascribed to the reducibility of Si-NPA. The reason for the appearance of CdO is indistinct and the related work will be done in the future. The blue, green and red emissions are ascribed to the silicon oxide layer, band gap of nc-CdS and the sulphur vacancies, respectively. Redshift and blueshift with the annealing temperature about green emissions are contributed to quantum size effect and the st...Physics Letters AjournalsFri, 19 Jul 2019 21:06:29 +0100712056354The median-based resolution of the St. Petersburg paradox
https://medworm.com/711744925/the-median-based-resolution-of-the-st-petersburg-paradox/
Publication date: Available online 17 July 2019Source: Physics Letters AAuthor(s): Takuya Okabe, Momoka Nii, Jin YoshimuraAbstractThe St. Petersburg Paradox contributed to establishing expected utility theory by demonstrating that decision making based on the expectation (expected value, or mean, average) leads to an unreasonable behavior. Although the expected value is commonly used as an optimization criterion in various fields of mathematical sciences, such paradoxical problems as arbitrariness and intransitivity have led many researchers to forsake expected utility theory in search of more useful alternatives. Here we show an analytical solution of the St. Petersburg Paradox based on the median of the probability distribution. The present method provides a reasonable solution to any re...Physics Letters AjournalsThu, 18 Jul 2019 16:12:24 +0100711744925Frictional effect on stability of discontinuity interface in tangential velocity of a shallow-water flow
https://medworm.com/711744924/frictional-effect-on-stability-of-discontinuity-interface-in-tangential-velocity-of-a-shallow-water-/
Publication date: Available online 17 July 2019Source: Physics Letters AAuthor(s): Liangbing Jin, Lê Thị Thái, Yasuhide FukumotoAbstractWe examine a frictional effect on the linear stability of an interface of discontinuity in tangential velocity. The fluid is moving with uniform velocity U in a region but is at rest in the other, and the bottom surface is assumed to exert drag force, quadratic in velocity, on the thin fluid layer. In the absence of the drag, the instability of the Kelvin-Helmholtz type is suppressed for U>8c, with c being the propagating speed of the gravity wave. We find by asymptotic analyses for both small and large values of the drag strength that the drag, regardless of its strength, makes the flow unstable for the whole range of the Froude number U/c. (Source: P...Physics Letters AjournalsThu, 18 Jul 2019 16:12:24 +0100711744924Detecting nonclassicality of light via Lieb's concavity
https://medworm.com/711744923/detecting-nonclassicality-of-light-via-liebs-concavity/
Publication date: Available online 17 July 2019Source: Physics Letters AAuthor(s): Shunlong Luo, Yue ZhangAbstractNonclassical light states are important for both conceptual and practical reasons: they are basic ingredients in testing and exploring quantum foundations, and are crucial resources in quantum technologies. Various useful criteria have been developed to detect nonclassicality in the literature, and several meaningful measures of nonclassicality have been introduced and measured experimentally. In this work, by use of a non-Hermitian generalization of the Wigner-Yanase-Dyson skew information and playing with operator ordering in evaluating average photon number, we develop a novel family of criteria for detecting nonclassicality of light based on Lieb's concavity, which is a dee...Physics Letters AjournalsThu, 18 Jul 2019 16:12:24 +0100711744923Manipulation of dielectric, ferroelectric and magnetic anomalies in multiferroic, morphotropic phase boundary quenched BiFeO3-0.35PbTiO3 solid solutions
https://medworm.com/711433267/manipulation-of-dielectric-ferroelectric-and-magnetic-anomalies-in-multiferroic-morphotropic-phase/
Publication date: Available online 16 July 2019Source: Physics Letters AAuthor(s): Layiq Zia, G. Hassnain Jaffari, Jamil Ur Rahman, Soonil Lee, S. Ismat ShahAbstractThe effect of thermal quenching on physical properties of morphotropic phase boundary BiFeO3-0.35PbTiO3 composition, composed of Pnma, R3c and P4mm phases, has been investigated in detail. We detected and quantified role of quenching through investigation of magnetic, dielectric and ferroelectric anomalies. Quenching significantly i) enhances the tetragonal phase percentage (hence affects domain structure), ii) reduces domain wall clamping with a large increase in electrical polarization, iii) increases magnetization at the structural phase transition temperature (tunable magneto-electric coupling), iv) magnifies intrinsic prop...Physics Letters AjournalsWed, 17 Jul 2019 11:15:32 +0100711433267A numerical method for fractional Schrödinger equation of Lennard-Jones potential
https://medworm.com/710502721/a-numerical-method-for-fractional-schrdinger-equation-of-lennard-jones-potential/
Publication date: Available online 12 July 2019Source: Physics Letters AAuthor(s): Marwan Al-Raeei, Moustafa Sayem El-DaherAbstractDepending on fractional analysis, we find a numerical algorithm to solve the time-independent fractional Schrödinger equation in case of Lennard-Jones potential in one dimension. We apply the algorithm for multiple values of the fractional parameter of the space-dependent fractional Schrödinger equation and multiple values of the system's energy to find the wave function and the probability in these cases. (Source: Physics Letters A)Physics Letters AjournalsSat, 13 Jul 2019 22:06:23 +0100710502721Hole doped α-MgAgSb as potential low temperature thermoelectric materials
https://medworm.com/710502720/hole-doped-mgagsb-as-potential-low-temperature-thermoelectric-materials/
Publication date: Available online 12 July 2019Source: Physics Letters AAuthor(s): Gang Zhou, Ji-wen Xu, Guang-hui RaoAbstractThe electronic structures and thermoelectric transport properties of α-MgAgSb were systematically investigated by using the first principles calculations combined with the Boltzmann transport equations. It is found that the thermoelectric properties of p-type α-MgAgSb are much better than those of n-type one, which originates from the steeper slope of the density of states at the edge of the valence band. By analyzing the density of states and partial charge density, we conclude that p-doping at the Mg-site does not modify the electronic states, but can optimize the carrier concentration. The effects of the carrier concentration and temperature on the thermoelectr...Physics Letters AjournalsSat, 13 Jul 2019 22:06:23 +0100710502720Evolution of cooperation in the spatial public goods game with the third-order reputation evaluation
https://medworm.com/710502719/evolution-of-cooperation-in-the-spatial-public-goods-game-with-the-third-order-reputation-evaluation/
Publication date: Available online 12 July 2019Source: Physics Letters AAuthor(s): Yang Wenpan, Juan Wang, Chengyi XiaAbstractIn this letter, in order to deeply explore the role of individual reputation in the evolutionary game dynamics, we present a new third-order reputation evaluation model to discuss the evolution of cooperation in the spatial public goods game. In the current model, we should not only consider the strategy (cooperation, C or defection, D) of a focal player, but also take his own reputation and his opponent's reputation status into account. Among them, the individual reputation will be divided into being good and bad according to the specified threshold, and the good player will be endowed with the more influential strategy transfer ability, which further helps to crea...Physics Letters AjournalsSat, 13 Jul 2019 22:06:23 +0100710502719Magnetic transitions in delafossite CuFeO2: A magnetocaloric effect study
https://medworm.com/710502718/magnetic-transitions-in-delafossite-cufeo2-a-magnetocaloric-effect-study/
Publication date: Available online 12 July 2019Source: Physics Letters AAuthor(s): Lei Zhang, Bernard A. Goodman, DingKang Xiong, Wen DengAbstractCuFeO2 was synthetized by a solid-state reaction and its low temperature magnetic properties investigated using the magnetocaloric effect. Magnetic susceptibility measurements show that there are two magnetic transition temperatures at about 16 and 11 K. Measurement of isothermal magnetization curves for different applied magnetic fields near these temperatures show a reversal in the magnetization trend around 11 K, and Arrott plots indicate they are accompanied by second- and first-order magnetic phase transitions, respectively. Both normal and inverse magnetocaloric effects are observed, and the maximum magnetic entropy change is obtained at 11...Physics Letters AjournalsSat, 13 Jul 2019 22:06:23 +0100710502718Design of a negative group delay filter via reservoir computing approach: Real-time prediction of chaotic signals
https://medworm.com/710190843/design-of-a-negative-group-delay-filter-via-reservoir-computing-approach-real-time-prediction-of-ch/
Publication date: Available online 11 July 2019Source: Physics Letters AAuthor(s): Tatjana Pyragiene, Kestutis PyragasAbstractAn optimal arbitrary order filter with negative group delay is proposed for a real-time prediction of complex band-limited signals. The filter consists of a set of second-order linear dissipative oscillators and is determined by a rational transfer function with fixed poles and optimized zeros. The filter design and optimization algorithm is based on a reservoir computing approach. The predictive properties of the filter are demonstrated numerically for two chaotic model systems — the finite-dimensional Rössler system and the infinite-dimensional Mackey-Glass system, as well as for the real biological signal of the fingertip photoplethysmogram. (Source: Physics L...Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190843Band alignment regulation of HfO2/SiC heterojunctions induced by PEALD with in situ NH3-plasma passivation
https://medworm.com/710190842/band-alignment-regulation-of-hfo2sic-heterojunctions-induced-by-peald-with-in-situ-nh3-plasma-passi/
Publication date: Available online 11 July 2019Source: Physics Letters AAuthor(s): Dawei Xu, Li Zheng, Xinhong Cheng, Gang Wang, Qian Wang, Wenbo Xin, Peiyi Ye, Lingyan Shen, Yuehui YuAbstractThe efficient passivation of in situ NH3-plasma pre-treatment and its regulation of the band alignment between HfO2 and 4H-SiC have been investigated by XPS. With in situ NH3-plasma passivation by PEALD, a VBO of 0.72 eV and a CBO of 1.54 eV can be obtained across the HfO2/4H-SiC interface. The Si-O bonds components reduction in the passivated interface layers will lead to band bending or band shift at the interface and regulate the band alignments between HfO2 and 4H-SiC. The physical mechanism investigation of band alignments can be a cornerstone for the application of HfO2/4H-SiC heterojunctions in...Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190842Experimental study of the effect of propellant asymmetrical distribution on anode current in a Hall effect thruster
https://medworm.com/710190841/experimental-study-of-the-effect-of-propellant-asymmetrical-distribution-on-anode-current-in-a-hall-/
Publication date: Available online 11 July 2019Source: Physics Letters AAuthor(s): Minghao Ding, Hong Li, Yongjie Ding, Hui Liu, Daren Yu, Xiaogang WangAbstractThis paper experimentally evaluated the effect of the disruption of the symmetrical distribution of the propellant on the characteristics of the anode current. The change in the asymmetry degree of the propellant distribution is achieved by supplying gas with a dual-cavity gas distributor. The results show that as the asymmetry degree increases, the magnitude of the anode current changes monotonically from a slow growth to a rapid growth, while the peak-to-peak value of the anode current exhibits a non-monotonic behavior. A preliminary analysis shows that the asymmetrical distribution of the propellant causes a nonuniform plasma gen...Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190841The occurrence of multistability and normal mode splitting in an optomechanical system
https://medworm.com/710190840/the-occurrence-of-multistability-and-normal-mode-splitting-in-an-optomechanical-system/
Publication date: Available online 11 July 2019Source: Physics Letters AAuthor(s): Kamran UllahAbstractWe provide a theoretical technique to study the occurrence of multistability and normal mode splitting in an optomechanical system driven by a single mode cavity field. For this purpose, we consider the position-dependent mass mechanical resonator (PDMR) which produces the nonlinearity in the system. This shifts the system from monostable to bistable regime and bistable to a multistable regime at different conditions of the nonlinearity. Further, we use the Fourier transform technique to find out the fluctuation in the position of the nano-mechanical resonator and their energy spectrum as well. Moreover, we used the input-output theory to analyze the transmitted field spectrum as well as ...Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190840A novel anode attachment mode in argon-helium free-burning arcs at atmospheric pressure
https://medworm.com/710190839/a-novel-anode-attachment-mode-in-argon-helium-free-burning-arcs-at-atmospheric-pressure/
Publication date: Available online 11 July 2019Source: Physics Letters AAuthor(s): Cheng Wang, Qiang Sun, Zelong Zhang, Weidong XiaAbstractAn argon-helium free-burning arc that operates on a graphite anode is investigated. Images of the arc and anode attachment under different arc currents and different helium ratios are exhibited. Experimental results show that both the arc and anode attachment are characterized by demixing. Moreover, an annular dark region surrounding the anode center is observed in the anode attachment region under the conditions of a higher arc current and a higher helium ratio, which is similar to the self-organized anode attachment mode in glow discharges. Preliminary analysis indicates that the arc demixing, the thermophysical properties of the mixture gas, and the ...Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190839Photonic band structure in a two-dimensional hexagonal lattice of equilateral triangles
https://medworm.com/710190838/photonic-band-structure-in-a-two-dimensional-hexagonal-lattice-of-equilateral-triangles/
Publication date: Available online 11 July 2019Source: Physics Letters AAuthor(s): Francis Segovia-Chaves, Herbert Vinck-Posada, Erik Navarro-BarónAbstractIn this paper, the plane wave expansion method is used to calculate the photonic band structure (PBS) for the transverse electric (TE) polarization in a two-dimensional hexagonal lattice composed air holes with cross-sections in the shape of equilateral triangles embedded in a GaAs background. We consider that the dielectric constant of GaAs is dependent on both hydrostatic pressure and temperature. Further, an increase can be observed in the width of the photonic band gap (PBG) while the lengths of the sides of the equilateral triangles are increased. When the pressure increases in the presence of a constant temperature, the dielectric...Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190838Dynamics to the universal structure of one-dimensional self-gravitating systems in the quasi-equilibrium state
https://medworm.com/710190837/dynamics-to-the-universal-structure-of-one-dimensional-self-gravitating-systems-in-the-quasi-equilib/
We present a phenomenological model to describe the universal structure by using a special Langevin equation with a distinctive random noise to self-gravitating systems. Additionally, we unveil a mechanism which decides the radius of the system. (Source: Physics Letters A)Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190837The single-polarization filter composed of gold-coated photonic crystal fiber
https://medworm.com/710190836/the-single-polarization-filter-composed-of-gold-coated-photonic-crystal-fiber/
Publication date: Available online 11 July 2019Source: Physics Letters AAuthor(s): Chao Liu, Liying Wang, Lin Yang, Famei Wang, Chunhong Xu, Jingwei Lv, Guanglai Fu, Xianli Li, Qiang Liu, Haiwei Mu, Tao Sun, Paul K. ChuAbstractA single-polarization filter comprising a gold-coated photonic crystal fiber based on surface plasmon resonance is designed and investigated. The pattern matching and coupled polarization characteristics analyzed by the full-vector finite element method (FEM) and losses at 1,540 nm are achieved to 1,016.01739 dB/cm (x-pol core mode) and 33.81917 dB/cm (y-pol core mode). The crosstalk (CT) value of the 1,540 nm band is −853.12653 dB for fiber length L=1,000 μm and the bandwidth is 850 nm. The working wavelength of the filter ranges from 1,280 nm to 1,540 nm by var...Physics Letters AjournalsFri, 12 Jul 2019 17:12:26 +0100710190836Integral invariants for non-barotropic flows in a four dimensional space time manifold
https://medworm.com/710035386/integral-invariants-for-non-barotropic-flows-in-a-four-dimensional-space-time-manifold/
Publication date: Available online 10 July 2019Source: Physics Letters AAuthor(s): Susan Mathew Panakkal, M.J. VedanAbstractProperties of non-barotropic flows are described using Lie derivatives of differential forms in a Euclidean four dimensional space-time manifold. Vanishing of the Lie derivative implies that the corresponding physical quantity remains invariant along the integral curves of the flow. Integral invariants of non-barotropic perfect and viscous flows are studied using the concepts of relative and absolute invariance of forms. The four dimensional expressions for the rate of change of the generalized circulation, generalized vorticity flux, generalized helicity and generalized parity in the case of ideal and viscous non-barotropic flows are thereby obtained. (Source: Physic...Physics Letters AjournalsFri, 12 Jul 2019 02:42:33 +0100710035386Ground states of spin-orbit-coupled Bose Einstein condensates in the presence of external magnetic field
https://medworm.com/710035385/ground-states-of-spin-orbit-coupled-bose-einstein-condensates-in-the-presence-of-external-magnetic-f/
Publication date: Available online 10 July 2019Source: Physics Letters AAuthor(s): Rui-Fang Zhang, Yongping Zhang, Lu LiAbstractTwo different kinds of spin-orbit (SO) coupling are often investigated theoretically and experimentally in atomic Bose-Einstein condensates (BECs), namely, Rashba and Dresselhaus SO couplings. We show that ground states for these two SO-coupled BECs share lots of similarities and it is impossible to distinguish them from the observation of ground states. We find that an Ioffe-Pritchard magnetic field can be utilized as a tool to distinguish them. In the presence of the Ioffe-Pritchard magnetic field, ground states manifest distinctively for the Rashba and Dresselhaus SO-coupled BECs. (Source: Physics Letters A)Physics Letters AjournalsFri, 12 Jul 2019 02:42:33 +0100710035385Statistical description of multiple collisions in the Fermi-Ulam model
https://medworm.com/710035384/statistical-description-of-multiple-collisions-in-the-fermi-ulam-model/
Publication date: Available online 10 July 2019Source: Physics Letters AAuthor(s): Diogo Ricardo da Costa, Mario R. Silva, Edson D. Leonel, J.A. Méndez-BermúdezAbstractThe Fermi-Ulam model consists of a point particle colliding elastically between two hards walls, one is considered fixed and the other one oscillates periodically in time. Most investigations on this model are based on a map approach that, although it is extremely efficient from the computational point of view, ignores processes which are relevant for a thorough dynamical description. The map approach considers the so called static wall approximation. In this paper, by efficiently solving the exact Fermi-Ulam model, we statistically characterize multiple collisions with the moving wall (processes not considered in the stat...Physics Letters AjournalsFri, 12 Jul 2019 02:42:33 +0100710035384Unambiguous discrimination of nonorthogonal entangled quantum states in cavity QED
https://medworm.com/710035383/unambiguous-discrimination-of-nonorthogonal-entangled-quantum-states-in-cavity-qed/
Publication date: Available online 10 July 2019Source: Physics Letters AAuthor(s): R.J. de Assis, J.S. Sales, N.G. de AlmeidaAbstractIn this work we propose a scheme in the context of superconducting cavities to unambiguously discriminate non-orthogonal quantum field states when one of them is one of the four Bell states. The present work, which generalizes an earlier proposal [1] dealing with non-entangled states, also makes use of a single high Q cavity, a sample of three-level atoms, Ramsey zones and selective detectors, thus consisting of an oversimplification from the experimental view. (Source: Physics Letters A)Physics Letters AjournalsFri, 12 Jul 2019 02:42:33 +0100710035383GPU-based DPSO algorithm for structural optimization of Pt-Co bimetallic nanoparticles
https://medworm.com/710035382/gpu-based-dpso-algorithm-for-structural-optimization-of-pt-co-bimetallic-nanoparticles/
Publication date: Available online 10 July 2019Source: Physics Letters AAuthor(s): Gui-Fang Shao, Jian-Bo Yang, Jun-Fa Zhang, Tun-Dong Liu, Yu-Hua WenAbstractAlloy nanoparticles (NPs) are potential candidates for catalysts in fuel cells applications, and their physical properties are associated with the corresponding stable structures. In this work, a GPU-based discrete particle swarm optimization (DPSO) method is designed to investigate the stable structure of Pt-Co alloy NPs. Register and an optimal block design are used to further increase the acceleration ratio. Comparative experiments on CPU and GPU show that the GPU-based DPSO algorithm possesses superior computational performance, and Register has a great influence on the acceleration ratio. Analyses on the stable structures of Pt-C...Physics Letters AjournalsFri, 12 Jul 2019 02:42:33 +0100710035382Nonlinear bandgap properties in a nonlocal piezoelectric phononic crystal nanobeam
https://medworm.com/709727116/nonlinear-bandgap-properties-in-a-nonlocal-piezoelectric-phononic-crystal-nanobeam/
Publication date: Available online 9 July 2019Source: Physics Letters AAuthor(s): Denghui Qian, Zhiyu Shi, Chengwei Ning, Jianchun WangAbstractApplying nonlocal elasticity theory, von Kármán type nonlinear strain-displacement relation and plane wave expansion (PWE) method to Euler-Bernoulli beam, the calculation method of band structure of a nonlinear nonlocal piezoelectric phononic crystal (PC) nanobeam is proposed and formulized. In order to investigate the properties of wave propagating in the nanobeam in detail, band gaps of first four orders are picked, and the corresponding influence rules of electro-mechanical coupling fields, nonlocal effect and geometric parameters on band gaps are studied. During the researches, external electrical voltage and axial force are chosen as the infl...Physics Letters AjournalsWed, 10 Jul 2019 21:42:31 +0100709727116Temperature-dependent XAFS study of the local lattice distortion of the CuO2 plane in Sr2CuO3+δ powder sample
https://medworm.com/709727115/temperature-dependent-xafs-study-of-the-local-lattice-distortion-of-the-cuo2-plane-in-sr2cuo3-pow/
Publication date: Available online 9 July 2019Source: Physics Letters AAuthor(s): Haibo Wang, Ying Liu, Zhenlin Luo, Qingqing Liu, Yuanjun Yang, Haoliang Huang, Mengmeng Yang, Changqing Jin, Chen GaoAbstractIn order to study the relationship between local lattice distortion and superconductivity, we performed temperature dependent x-ray absorption fine structure (XAFS) on Sr2CuO3+δ powder sample (single phase with Tc=48 K). The temperature dependent Debye-Waller factor of Cu-O pair appears an anomalous upturn at 90 K and becomes drop around the superconducting transition temperature of ∼50 K. It means that local lattice distortion appears at 90 K. Furthermore, the analysis of temperature dependent X ray Absorption Near Edge Structure (XANES) shows that the R factor, which denotes the in...Physics Letters AjournalsWed, 10 Jul 2019 21:42:31 +0100709727115Characterization of a Planar NID Chiral Interface under Negative and/or Positive Phase Velocity Conditions
https://medworm.com/709422185/characterization-of-a-planar-nid-chiral-interface-under-negative-andor-positive-phase-velocity-cond/
Publication date: Available online 8 July 2019Source: Physics Letters AAuthor(s): Samra Kanwal, Qaisar Abbas NaqviAbstractUsing positive and/or negative phase velocity conditions, characteristics of a planar non-integer dimensional (NID) chiral interface are explored for specific values of NID parameter. For this purpose, discussion is divided into four cases. It is noted how characteristics of the interface changes when the situation is changed from one case to another. Impact of variation of NID parameter on the reflected power is also noted for each case. (Source: Physics Letters A)Physics Letters AjournalsTue, 09 Jul 2019 16:42:28 +0100709422185Nanophotonic on-chip hybrid plasmonic electro-optic modulator with phase change materials
https://medworm.com/709422184/nanophotonic-on-chip-hybrid-plasmonic-electro-optic-modulator-with-phase-change-materials/
Publication date: Available online 8 July 2019Source: Physics Letters AAuthor(s): Mandeep Singh, Sanjeev Kumar Raghuwanshi, T. SrinivasAbstractA vertical hybrid plasmonic waveguide (HPWG) modulator incorporating Au nano-rings and operating in the near-infrared (NIR) band is proposed using phase change chalcogenide thin film (Ge2Sb2Te5, commonly known as GST). It is shown that with amorphous to crystalline phase transition of GST, significant modulation depths can be achieved in the optical C-band. Further, localized surface plasmon resonance (LSPR) excitations from the Au nano-ring embedded in the low-indexed slot region is used to enhance the overall performance of the reported GST based electro-optic modulator. In addition, significant wavelength shifts, and improved extinction ratio (ER...Physics Letters AjournalsTue, 09 Jul 2019 16:42:28 +0100709422184Spin and spin-valley Hall effects in a honeycomb lattice with antiferromagnetism and spin-orbit couplings
https://medworm.com/709422183/spin-and-spin-valley-hall-effects-in-a-honeycomb-lattice-with-antiferromagnetism-and-spin-orbit-coup/
Publication date: Available online 8 July 2019Source: Physics Letters AAuthor(s): Jianfei Zou, Yinghan Yuan, Jing KangAbstractWe study linear response to a longitudinal electric field on an antiferromagnetic honeycomb lattice with intrinsic and Rashba spin-orbit couplings (SOCs). It is found that the spin-valley Hall effect could emerge alone or coexist with the spin Hall effect. The spin and spin-valley Hall conductivities exhibit some peculiarities that depend on the distinct topological states of the graphene lattice. Furthermore, the spin and spin-valley Hall conductivities could be remarkably modulated by changing the Fermi level. Our findings suggest that the antiferromagnetic honeycomb lattice with SOCs is an excellent platform for potential applications of spintronics and valleytro...Physics Letters AjournalsTue, 09 Jul 2019 16:42:28 +0100709422183Higher-order solutions of a matrix AKNS system associated with a Hermitian symmetric space
https://medworm.com/709422182/higher-order-solutions-of-a-matrix-akns-system-associated-with-a-hermitian-symmetric-space/
Publication date: Available online 8 July 2019Source: Physics Letters AAuthor(s): Xianguo Geng, Jing Shen, Bo XueAbstractIn this paper, we study a matrix Ablowitz–Kaup–Newell–Segur (AKNS) system associated with a Hermitian symmetric space as a follow-up study of an earlier paper. A multi-fold generalized Darboux transformation of the matrix AKNS system associated with a Hermitian symmetric space is constructed by means of determinants. Subsequently, we derive various higher-order solutions for this system, including fan-shaped rogue wave and (truncated) Kuznetsov–Ma breather solutions. Specifically, we show the fusion and fission processes for two truncated Kuznetsov–Ma breathers by taking different free parameters. (Source: Physics Letters A)Physics Letters AjournalsTue, 09 Jul 2019 16:42:28 +0100709422182Core-shell quantum dot electron bubbles as exotic ions in superfluid liquid 4He
https://medworm.com/709422181/core-shell-quantum-dot-electron-bubbles-as-exotic-ions-in-superfluid-liquid-4he/
Publication date: Available online 8 July 2019Source: Physics Letters AAuthor(s): Nabil M. LawandyAbstractA number of experiments in superfluid helium-4 over the past fifty years on the mobility of electron bubbles, which are unique quantum dots in the liquid state, revealed the existence of a “fast” ion and other “exotic” negative ions whose origin and structure still remains unresolved. The fast ion has a mobility which is six times that of the well understood single electron bubble and the other ions span a region from the fast ion mobility to that of the electron bubble. The work presented here shows that a net anionic, two electron, core-shell quantum dot could potentially explain these findings and provide direction for new experimental work. The model described is based on t...Physics Letters AjournalsTue, 09 Jul 2019 16:42:28 +0100709422181Editors
https://medworm.com/709422136/editors/
Publication date: 12 August 2019Source: Physics Letters A, Volume 383, Issue 23Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 09 Jul 2019 16:42:28 +0100709422136Effect of the weak interaction on the in situ radii of condensate boson atoms in one or two-dimensional deep optical lattices
https://medworm.com/709270283/effect-of-the-weak-interaction-on-the-in-situ-radii-of-condensate-boson-atoms-in-one-or-two-dimensio/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): Ahmed S. Hassan, Azza M. El-Badry, Alyaa A. Mahmoud, Hend A. Abdel-Gany, Adel M. Mohammedein, A.M. AbdallahAbstractIn this letter we suggest a theoretical model to investigate the weak interaction dependence of the in situ radii of condensate boson atoms in a combined harmonic with one or two-dimensional deep optical lattice. The semiclassical approximation is employed to calculate the above mentioned parameters. The calculated results showed that the in situ radii depends crucially on the interatomic interaction. Our results can be extended to investigate the moment of inertia of condensate boson atoms in combined harmonic-optical potential as well as superfluidity nature of synthetically charged boson atoms...Physics Letters AjournalsTue, 09 Jul 2019 02:06:35 +0100709270283Anisotropic Keldysh interaction
https://medworm.com/708815086/anisotropic-keldysh-interaction/
Publication date: Available online 5 July 2019Source: Physics Letters AAuthor(s): Andrei GaliautdinovAbstractWe generalize the classic calculations by Rytova and Keldysh of screened Coulomb interaction in semiconductor thin films to systems with anisotropic permittivity tensor. Explicit asymptotic expressions for electrostatic potential energy of interaction in the weakly anisotropic case are found in closed analytical form. The case of strong in-plane anisotropy, however, requires evaluation of the inverse Fourier transform of 1/(k+Akx2+Bky2), which, at present, remains unresolved. (Source: Physics Letters A)Physics Letters AjournalsSun, 07 Jul 2019 06:15:27 +0100708815086Stability boundaries of a Mathieu equation having PT symmetry
https://medworm.com/708510821/stability-boundaries-of-a-mathieu-equation-having-pt-symmetry/
Publication date: Available online 4 July 2019Source: Physics Letters AAuthor(s): P.A. BrandãoAbstractI have applied multiple-scale perturbation theory to a generalized complex PT-symmetric Mathieu equation in order to find the stability boundaries between bounded and unbounded solutions. The analysis suggests that the non-Hermitian parameter present in the equation can be used to control the shape and curvature of these boundaries. Although this was suggested earlier by several authors, analytic formulas for the boundary curves were not given. This paper is a first attempt to fill this gap in the theory. (Source: Physics Letters A)Physics Letters AjournalsSat, 06 Jul 2019 01:36:29 +0100708510821Conductance of inhomogeneous Luttinger liquids with a finite bandwidth
https://medworm.com/708510820/conductance-of-inhomogeneous-luttinger-liquids-with-a-finite-bandwidth/
Publication date: Available online 4 July 2019Source: Physics Letters AAuthor(s): Joy Prakash Das, Girish S. SetlurAbstractThe finite-bandwidth conductance of a Luttinger liquid (LL) with a cluster of impurities is studied and its variation with respect to temperature is shown. The calculations are done using the correlation functions obtained using the powerful non-chiral bosonization technique (NCBT). The results are compared with those obtained by Matveev, Yue and Glazman [K. Matveev et al., Phys. Rev. Lett. 71, 3351 (1993)] who deal with a weakly interacting LL. By contrast, NCBT correctly provides the conductance for all values of the interaction strength (as well as the sign). In addition to finding perfect agreement with the results of Matveev et al. for both weakly repulsive and we...Physics Letters AjournalsSat, 06 Jul 2019 01:36:29 +0100708510820Impacts of phase transformation on the thermoelectric properties of ZnO nanowires
https://medworm.com/708358310/impacts-of-phase-transformation-on-the-thermoelectric-properties-of-zno-nanowires/
Publication date: Available online 3 July 2019Source: Physics Letters AAuthor(s): Lihong Shi, Jia He, Dengfeng LiAbstractImpacts of phase transformation from regular wurtzite phase to a graphitic polymorph hexagonal phase under tensile loading, on the thermoelectric properties of Zinc oxide nanowires (ZnO NWs), which is oriented in the [0001] direction, are studied by combining the first-principles simulation with one-dimensional (1D) Boltzmann transport equation (BTE). Our results show that this phase transformation has greatly influenced the thermoelectric properties of the ZnO NWs. We also find that the largest value of figure of merit ZT achieved for hexagonal phase (H phase) is larger than that for wurtzite phase (W phase) in the temperature range (200 K-1000 K), which means that hexa...Physics Letters AjournalsFri, 05 Jul 2019 11:12:34 +0100708358310Low bias negative differential resistance with dual-peaks based on octacene molecular device
https://medworm.com/708358309/low-bias-negative-differential-resistance-with-dual-peaks-based-on-octacene-molecular-device/
Publication date: Available online 3 July 2019Source: Physics Letters AAuthor(s): J. Zhang, Z. Qin, B. Xu, G. SongAbstractBased on non-equilibrium Green's function and density functional theory, a first-principles study of the transport properties of a molecular device is performed. This device is composed of two octacene molecules separated by a ethyl barrier, which are then linked to Ag leads through thiolates. The device shows low bias negative differential resistance effect with dual-peaks, which may be useful for designing molecular devices with low power-dissipation and multi-function in the future. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Jul 2019 11:12:34 +0100708358309Phase transitions in normalized cut of social networks
https://medworm.com/708358308/phase-transitions-in-normalized-cut-of-social-networks/
Publication date: Available online 3 July 2019Source: Physics Letters AAuthor(s): Wei Lin, Min Li, Shuming Zhou, Jiafei Liu, Gaolin Chen, Zhengdong GuAbstractOne of the main goals of network analysis and data science is to identify community structures in a network. Community structure is a typical feature of social networks and community detection is considered to be crucial to understand the structure and function of social networks in cyberspace. The community detection problem of social networks can be viewed as a graph partitioning problem whose objective is to identify the external edges as the edge cut that separates the network as two subnetworks by recursive method. The degree-normalized adjacency matrix is more convenient than traditional Laplacian matrix in calculating eigenvalu...Physics Letters AjournalsFri, 05 Jul 2019 11:12:34 +0100708358308The electronic structures and properties for carbon doped aluminum phosphide
https://medworm.com/708358307/the-electronic-structures-and-properties-for-carbon-doped-aluminum-phosphide/
Publication date: Available online 3 July 2019Source: Physics Letters AAuthor(s): S.W. Fan, L. Yang, G.Y. GaoAbstractBased on the first-principle method, the effects of carbon dopants on AlP are studied. Our investigations indicate carbons substituting aluminum (CAl) or phosphorus (CP) cannot induce the AlP to be magnetic system. The AlP with CAl defects shows n-type metallic characteristic. As the carbons forming the interstitial doped configurations (Cint), a few percent of Cint could induct the AlP to be a half-metallic ferromagnet, and the half-metallic gaps could reach 0.45∼0.48 eV. Mean field theory predicts the Curie temperature for Cint doped configurations would be above room temperature. Formation energies indicate that Cint, CAl and CP defects could be realized experimentally....Physics Letters AjournalsFri, 05 Jul 2019 11:12:34 +0100708358307Approximate bound state solutions of the Klein-Gordon equation with the linear combination of Hulthén and Yukawa potentials
https://medworm.com/707898623/approximate-bound-state-solutions-of-the-klein-gordon-equation-with-the-linear-combination-of-hulth/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): A.I. Ahmadov, S.M. Aslanova, M.Sh. Orujova, S.V. Badalov, Shi-Hai DongAbstractBased on a developed scheme we show how to deal with the centrifugal term and the Coulombic behavior part and then to solve the Klein-Gordon (KG) equation for the linear combination of Hulthén and Yukawa potentials. Two cases, i.e., the scalar potential which is equal and unequal to vector potential, are considered for arbitrary l state. With the aid of the Nikiforov-Uvarov (NU) method and the traditional approach, we present the eigenvalues and the corresponding radial wave functions expressed by the Jacobi polynomials or hypergeometric functions and find that the results obtained by them are consistent. For given values of potent...Physics Letters AjournalsWed, 03 Jul 2019 16:12:25 +0100707898623Effect of the weak interaction on the in situ radii of condensate boson atoms in one and two deep optical lattices
https://medworm.com/707898621/effect-of-the-weak-interaction-on-the-in-situ-radii-of-condensate-boson-atoms-in-one-and-two-deep-op/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): Ahmed S. Hassan, Azza M. El-Badry, Alyaa A.Mahmoud, Hend A. Abdel-Gany, Adel M. Mohammedein, A.M. AbdallahAbstractIn this letter we suggest a theoretical model to investigate the weak interaction dependence of the in situ radii of condensate boson atoms in a combined harmonic one and two dimensions deep optical lattice. The semiclassical approximation is employed to calculate the above mentioned parameters. The calculated results showed that the in situ radii depends crucially on the interatomic interaction. Our results can be extended to investigate the moment of inertia of condensate boson atoms in combined harmonic-optical potential as well as superfludity nature of synthetically charged boson atoms in com...Physics Letters AjournalsWed, 03 Jul 2019 16:12:25 +0100707898621Dynamics and phase transitions in biased ladder systems with magnetic flux
https://medworm.com/707898620/dynamics-and-phase-transitions-in-biased-ladder-systems-with-magnetic-flux/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): Xin Qiao, Xiao-Bo Zhang, Ai-Xia Zhang, Zi-Fa Yu, Ju-Kui XueAbstractThe ground states and the dynamics of a biased two-leg flux ladder in the presence of a gravitational field are discussed. In the absence of the gravitational field, the ground states and the critical condition of phase transition are obtained analytically. We identify the Meissner phase, Vortex phase, and interestingly, two new Plane Wave phases, that break both Z2 and time-reversal symmetry, characterized by the imbalance particle density distribution, asymmetry double well energy band structure in Plane Wave I (PWI) phase and asymmetry single well energy band structure in Plane Wave II (PWII) phase, respectively. In the presence of a longit...Physics Letters AjournalsWed, 03 Jul 2019 16:12:25 +0100707898620Transmission coefficient of interacting few-body system in one dimensional space
https://medworm.com/707898619/transmission-coefficient-of-interacting-few-body-system-in-one-dimensional-space/
We present a novel way of defining transmission coefficient of one spatial dimensional few interacting electrons system. The formalism is based on the probability interpretation of unitarity of physical scattering S-matrix. The relation of our formalism to the well-established method for describing the conducting properties of non-interacting systems, Landauer-Büttiker formula, is discussed. The transport properties of interacting two-electron system is also discussed as a specific example of our formalism. (Source: Physics Letters A)Physics Letters AjournalsWed, 03 Jul 2019 16:12:25 +0100707898619Thermoelectric coefficient in nanoisland metallic films
https://medworm.com/707898616/thermoelectric-coefficient-in-nanoisland-metallic-films/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): A.P. Boltaev, F.A. Pudonin, I.A. Sherstnev, D.A. EgorovAbstractWe study the thermoelectric properties of island metal films on a dielectric substrate. Dependence of thermoelectric coefficient of metal films on their thickness with the dimensionless conductance g>1 and g<1 was investigated. Also, the thermopower dependence of island metal structures with g<1 on the chemical composition of nanostructures was studied. We found that regardless of tunneling or Drude character of conductivity, the value of the thermoelectric coefficient in island metal films is determined by the properties of film metal element. (Source: Physics Letters A)Physics Letters AjournalsWed, 03 Jul 2019 16:12:25 +0100707898616Dependence of valley polarization on Schottky metal stripe in magnetic-strain graphene
https://medworm.com/707898615/dependence-of-valley-polarization-on-schottky-metal-stripe-in-magnetic-strain-graphene/
This study is very useful for understanding and designing the valleytronic devices. (Source: Physics Letters A)Physics Letters AjournalsWed, 03 Jul 2019 16:12:25 +0100707898615Chirality, helicity and the rotational content of electromagnetic fields
https://medworm.com/707746600/chirality-helicity-and-the-rotational-content-of-electromagnetic-fields/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): M. Fernández GuastiAbstractThe chirality continuity equation in the presence of charge and current is obtained from the complementary fields formalism. In the presence of sources, it is strongly suggested that the chirality should be defined proportional to με(H⋅∂tE−E⋅∂tH) instead of the usual definition H⋅(∇×B)+εE⋅(∇×E). Both definitions are equivalent for free fields. The relationship between helicity ϱAC and chirality ϱEH for arbitrary wave solutions is shown to be ∂t2ϱAC=με(1εϱEH+A⋅∂t2B−C⋅∂t2E). The helicity continuity equation can be transformed into the chirality scheme via a time derivative transformation of all the field functions. Following a mechanical anal...Physics Letters AjournalsWed, 03 Jul 2019 02:12:40 +0100707746600Quantum repeated games with continuous-variable strategies
https://medworm.com/707746599/quantum-repeated-games-with-continuous-variable-strategies/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): Zhe Yang, Xian ZhangAbstractBy the Li-Du-Massar method, we investigate the quantization of a two-stage repeated duopoly game. By solving the quantum repeated game with continuous-variable strategies, we analyze the effect of two stages' entanglement levels, and give some numerical evidences to describe our model. (Source: Physics Letters A)Physics Letters AjournalsWed, 03 Jul 2019 02:12:40 +0100707746599Activating MoS2 basal planes for hydrogen evolution through the As doping and strain
https://medworm.com/707746598/activating-mos2-basal-planes-for-hydrogen-evolution-through-the-as-doping-and-strain/
Publication date: Available online 2 July 2019Source: Physics Letters AAuthor(s): Yi-Qi Yang, Chun-Xiang Zhao, Shou-Yan Bai, Cai-Ping Wang, Chun-Yao NiuAbstractAs a non-precious catalyst for the electrochemical hydrogen evolution reaction (HER), the two-dimensional MoS2 has been widely studied. To activate the MoS2 inert basal plane to enable optimal activity, high defect concentration of sulfur vacancies is needed. Herein, based on the first-principles calculations we demonstrate that the HER of MoS2 can be greatly enhanced by As doping and biaxial strain. We show that the As-doping sites are new catalytic sites and the bonding of H can be greatly enhanced. Moreover, the relative hydrogen adsorption free energy (ΔΔGH) can be further manipulated by the strain effect, which efficiently ad...Physics Letters AjournalsWed, 03 Jul 2019 02:12:40 +0100707746598Spin polarized carrier injection driven magneto-optical Kerr effect in Cr-doped ZnO nanorods
https://medworm.com/706973069/spin-polarized-carrier-injection-driven-magneto-optical-kerr-effect-in-cr-doped-zno-nanorods/
Publication date: Available online 28 June 2019Source: Physics Letters AAuthor(s): M. Malaidurai, B. Santosh Kumar, R. ThangavelAbstractHydrothermal growth of Cr doped ZnO nanorods (NRs) thin films was grown on glass substrates. The strong ferromagnetic (FM) and antiferromagnetic (AFM) ordering was observed in 3% and 7% of Cr doped samples. The optical excitation of the Cr doped ZnO NRs is responsible for injection of the spin-polarized carriers in the 3% Cr doped ZnO NRs through longitudinal magneto-optical Kerr effect (MOKE). We determined a negative anisotropic magnetoresistance (∼23%) originated from spin orbit coupling due to sp-d exchange interaction. we calculated the process of photon induced inverse spin Hall angle (θISHE∼3.94×10−2) close to the MOKE saturated rotation ang...Physics Letters AjournalsSun, 30 Jun 2019 02:12:25 +0100706973069Temperature-electric field hysteresis loop of multicaloric effects in PbZr0.8Ti0.2O3 thin films
https://medworm.com/706973068/temperature-electric-field-hysteresis-loop-of-multicaloric-effects-in-pbzr08ti02o3-thin-films/
Publication date: Available online 28 June 2019Source: Physics Letters AAuthor(s): F. Wang, T. Liu, C.L. Xie, Y. Liu, N.S. Ma, J. Duan, J.R. He, B. Li, B.L. Ou, Y. Ou, J.J. Cheng, Q. Liu, L.F. Liu, W. WangAbstractThe Multicaloric effect in the PbZr0.8Ti0.2O3 thin films is investigated with the application of sine wave electric field, dc electric field and stress using a phase field method combined with the thermodynamic analysis. The simulation results show that the adiabatic temperature change-electric field curve presents a shape of butterfly in the presence of the sine wave electric field. In order to detect the effect of the sine wave electric field, the multicaloric effect and the domain structures under the direct electric field and the sine wave electric field are compared. It is fo...Physics Letters AjournalsSun, 30 Jun 2019 02:12:25 +0100706973068Preferred states of open electronic systems
https://medworm.com/706658441/preferred-states-of-open-electronic-systems/
Publication date: Available online 27 June 2019Source: Physics Letters AAuthor(s): HaoXiang Jiang, Yu ZhangAbstractSystem-environment interaction may introduce dynamic destruction of quantum coherence, resulting in a special representation named as pointer states. In this work, pointer states of an open electronic system are studied. The decoherence effect is taken into account through two different ways which are Büttiker's virtual probe model and strong electron-phonon interaction in the polaron picture. The pointer states of the system with different coupling strength are investigated. The pointer states are identified by tracking the eigenstates of the density matrix in real-time propagation. It is found that the pointer states can emerge for arbitrary coupling strength. And the point...Physics Letters AjournalsFri, 28 Jun 2019 22:03:30 +0100706658441The exact solution for the free induction decay in a quasi-one-dimensional system in a multi-pulse NMR experiment
https://medworm.com/706658440/the-exact-solution-for-the-free-induction-decay-in-a-quasi-one-dimensional-system-in-a-multi-pulse-n/
Publication date: Available online 27 June 2019Source: Physics Letters AAuthor(s): G.A. Bochkin, E.B. Fel'dman, S.G. Vasil'evAbstractThe exact solution for the free induction decay in a one-dimensional system in the multi-pulse experiment is obtained at both high and low temperatures in the approximation of nearest neighbor interactions. The experimental investigation is performed on a quasi-one-dimensional system of 19F nuclear spins in a single crystal of fluorapatite. The theoretical results are in a good agreement with the obtained experimental data. (Source: Physics Letters A)Physics Letters AjournalsFri, 28 Jun 2019 22:03:30 +0100706658440Energy band modulation of GaAs/Al0.26Ga0.74As quantum well in 3D self-assembled nanomembranes
https://medworm.com/706658439/energy-band-modulation-of-gaasal026ga074as-quantum-well-in-3d-self-assembled-nanomembranes/
In this study, we investigate the modulation of energy band in 3D self-assembled nanomembranes containing GaAs/Al0.26Ga0.74As quantum wells (QWs). Photoluminescence (PL) characterizations demonstrate that the self-assembled structures have different optical transition properties and the modulation of the energy band is thus realized. Detailed spectral analyses disclose that the small strain change in structures with different curvatures cannot cause remarkable change in energy bands in Al0.26Ga0.74As layer. On the other hand, the optical transitions of GaAs QW layer is influenced by the strain evolution in term of light emission intensity. We also find the first order Stark effect in rolled-up nanomembrane with diameter of 150 μm, which is closely connected with the coupling effect betwee...Physics Letters AjournalsFri, 28 Jun 2019 22:03:30 +0100706658439Numerical investigation of a tunable metamaterial perfect absorber consisting of two-intersecting graphene nanoring arrays
https://medworm.com/706341819/numerical-investigation-of-a-tunable-metamaterial-perfect-absorber-consisting-of-two-intersecting-gr/
Publication date: Available online 26 June 2019Source: Physics Letters AAuthor(s): Chunlian Cen, Yubin Zhang, Cuiping Liang, Xifang Chen, Zao Yi, Tao Duan, Yongjian Tang, Xin Ye, Yougen Yi, Shuyuan XiaoAbstractIn this paper, we report a numerical investigation of tunable dual-band metamaterial perfect absorber (MMPA) consisting of two-intersecting graphene nanorings arrays. The optical absorption performance of absorber is dominated by the inner/outer radius of nanorings and center distance between the two nanorings. For the resonance modes λ1 and λ2, the sensitivity of probing the surrounding refractive index can reach 7.97 μm/RIU and 13.27 μm/RIU respectively. The absorption performance of the under-study graphene nanorings can be flexibly adjusted by modulating the Fermi level of gr...Physics Letters AjournalsThu, 27 Jun 2019 17:12:26 +0100706341819Physical meaning of the stretched exponential Kohlrausch function
https://medworm.com/706341818/physical-meaning-of-the-stretched-exponential-kohlrausch-function/
Publication date: Available online 26 June 2019Source: Physics Letters AAuthor(s): Alexander LukichevAbstractIn this paper the physical meaning of the empirical Kohlrausch-Williams-Watts (KWW) function is explained in terms of the linear oscillator theory. It is shown that the KWW function is a solution of the non-autonomous linear first order equation for an overdamped linear oscillator. From the linear oscillator model it follows that the KWW-type relaxation is the linear relaxation with a time (coordinate, stress, voltage, etc.) dependent dissipation of energy. The theoretical results are validated by measurements. A method for modeling KWW-type relaxation using simple electrical circuits is proposed.Graphical abstract (Source: Physics Letters A)Physics Letters AjournalsThu, 27 Jun 2019 17:12:26 +0100706341818Average versus maximal coherence
https://medworm.com/705081558/average-versus-maximal-coherence/
Publication date: Available online 21 June 2019Source: Physics Letters AAuthor(s): Shunlong Luo, Yuan SunAbstractCoherence is a fundamental feature of quantum mechanics and plays a crucial role in the quantum realm. The issue of quantification of coherence has received considerable interests in recent years, and a variety of coherence quantifiers have been introduced. With these measures, one can investigate coherence in a more quantitative way. Based on the Wigner-Yanase skew information, we evaluate average coherence of a state with respect to arbitrary mutually unbiased bases as well as with respect to all orthonormal bases, and demonstrate their equivalence. We further evaluate the maximum coherence, and reveal a remarkable fact that in high dimensions, the coherence of a generic state...Physics Letters AjournalsSat, 22 Jun 2019 22:09:36 +0100705081558Prediction of two-dimensional monochalcogenides: MoS and WS
https://medworm.com/704447543/prediction-of-two-dimensional-monochalcogenides-mos-and-ws/
Publication date: Available online 19 June 2019Source: Physics Letters AAuthor(s): Dhanshree Pandey, Aparna ChakrabartiAbstractUsing density functional theory, we explore the possibility of two monolayer monochalcogenides, namely, MoS and WS. From the energetics, buckled and puckered structures are found to be more probable configurations. Our results on cohesive energy and phonon dispersion predict that the buckled structures of both MoS and WS are stable. On the other hand, while the puckered structure of WS clearly shows a dynamical instability, the same for MoS may have a stable configuration. Charge analyses predict ionic-like bonding in these systems. Density of states and band structure reveal a non-magnetic metallic nature for MoS in the stable configurations. However, for the buck...Physics Letters AjournalsThu, 20 Jun 2019 12:36:26 +0100704447543Phase role of white TiO2 precursor in its reduction to black TiO2
https://medworm.com/704447542/phase-role-of-white-tio2-precursor-in-its-reduction-to-black-tio2/
Publication date: Available online 19 June 2019Source: Physics Letters AAuthor(s): Haiyang Hu, Yan Lin, Yun Hang HuAbstractBlack TiO2, which is a promising photocatalyst with enhanced visible light absorption, is a new semiconductor with a smaller band gap than white TiO2. The synthesis of black TiO2 has been focused on optimizing hydrogen treatment and exploring different reductants. However, in this work, it was experimentally demonstrated that the phase structure of white TiO2 precursor plays an important role in its reduction to black TiO2 by hydrogen treatment, namely, compared with anatase TiO2, rutile TiO2 is much easier to be reduced to black TiO2. This provides a new direction for synthesis approach of black TiO2. (Source: Physics Letters A)Physics Letters AjournalsThu, 20 Jun 2019 12:36:26 +0100704447542An improved quantum principal component analysis algorithm based on the quantum singular threshold method
https://medworm.com/704447541/an-improved-quantum-principal-component-analysis-algorithm-based-on-the-quantum-singular-threshold-m/
Publication date: Available online 20 June 2019Source: Physics Letters AAuthor(s): Jie Lin, Wan-Su Bao, Shuo Zhang, Tan Li, Xiang WangAbstractQuantum principal component analysis (qPCA) is a dimensionality reduction algorithm for getting the eigenvectors corresponding to top several eigenvalues of the data matrix and then reconstructing. However, qPCA can only construct the quantum state contains all the eigenvectors and eigenvalues. In this paper, we present an improved quantum principal component analysis (Improved qPCA) algorithm with a fixed threshold. We can reduce the singular value less than the threshold to 0 and obtain a target quantum state which can be used to get an output similar to qPCA after phase estimation. Compared with qPCA, our algorithm has only the target eigenvalues ...Physics Letters AjournalsThu, 20 Jun 2019 12:36:26 +0100704447541Topological nature of Hubbard bands in strongly correlated systems
https://medworm.com/704289950/topological-nature-of-hubbard-bands-in-strongly-correlated-systems/
Publication date: Available online 18 June 2019Source: Physics Letters AAuthor(s): V.Yu. Irkhin, Yu.N. SkryabinAbstractThe topological nature of the Mott-Hubbard state in strongly correlated systems is treated. These systems are described in terms of spin-charge separation, i.e. spinon-holon deconfinement in the gauge field. Analogies with the quantum Hall effect and Landau quantization are considered, the presence of the Chern-Simons term being important for proper description of the Hubbard splitting. Occurrence of topological frustrations with doping in an effective two-band model is demonstrated. The role of orbital degrees of freedom and possible occurrence of orbital currents are discussed. (Source: Physics Letters A)Physics Letters AjournalsWed, 19 Jun 2019 22:15:31 +0100704289950Chemical vapor deposition synthesis of Ge doped ZnO nanowires and the optical property investigation
https://medworm.com/704289949/chemical-vapor-deposition-synthesis-of-ge-doped-zno-nanowires-and-the-optical-property-investigation/
Publication date: Available online 19 June 2019Source: Physics Letters AAuthor(s): Ying LiangAbstractGe-doped ZnO nanowires with high quality were prepared with simple chemical vapor deposition method. The morphology, crystal structure and elemental distribution were characterized using SEM (scanning electron microscopy), HRTEM (high resolution transmission electron microscopy) and EDS (energy dispersive spectrometry) mapping approaches. The optical properties were investigated with combination of room-temperature CL (cathode ray luminescence) and variable temperature micro-PL methods. It is found for the first time that a tapered Ge doped nanowire exhibits a thickness-dependent spectrum shift under a cathode-ray excitation, which was interpreted by the electron-lattice interaction model a...Physics Letters AjournalsWed, 19 Jun 2019 22:15:31 +0100704289949Comparison of information-theoretic products and inequalities for the lowest bound and unbound electronic states of H2+ based on exact calculation
https://medworm.com/703972088/comparison-of-information-theoretic-products-and-inequalities-for-the-lowest-bound-and-unbound-elect/
Publication date: Available online 17 June 2019Source: Physics Letters AAuthor(s): Sergey A. AstashkevichAbstractA study of information-theoretic properties of molecular bond on the example of the ground (bound) 1sσg and the lowest excited (unbound) 2pσu states of H2+ was conducted. Data about general information-theoretic measures, information products (Cramér-Rao, Fisher-Shannon information, and LMC complexity) and their inequalities in position and momentum spaces as a function of internuclear distance R=0.2–20 a.u. were obtained by an exact numerical calculation of the wave function. A systematic correlation between these information products was established. It was found that LMC complexity is most sensitive and detailed among these information products. A clear correlation betwe...Physics Letters AjournalsTue, 18 Jun 2019 17:09:27 +0100703972088Electrically controllable spin transport in bilayer graphene with Rashba spin-orbit interaction
https://medworm.com/703176249/electrically-controllable-spin-transport-in-bilayer-graphene-with-rashba-spin-orbit-interaction/
Publication date: Available online 14 June 2019Source: Physics Letters AAuthor(s): Qingtian Zhang, Junsong Jiang, Kwok Sum ChanAbstractWe study the spin transport in bilayer graphene nanoribbons (BGNs) in the presence of Rashba spin-orbit interaction (SOI) and external gate voltages. It is found that the spin polarization can be significantly enhanced by the interlayer asymmetry or longitudinal mirror asymmetry produced by external gate voltages. Rashba SOI alone in BGNs can only generate current with spin polarization along the in-plane y direction, but the polarization components can be found along the x, y and z directions when a gate voltage is applied. High spin polarization with flexible orientation is obtained in the proposed device. Our findings shed new light on the generation of ...Physics Letters AjournalsSat, 15 Jun 2019 17:06:26 +0100703176249A no-go result for the quantum damped harmonic oscillator
https://medworm.com/703176248/a-no-go-result-for-the-quantum-damped-harmonic-oscillator/
Publication date: Available online 14 June 2019Source: Physics Letters AAuthor(s): F. Bagarello, F. Gargano, F. RoccatiAbstractIn this letter we show that it is not possible to set up a canonical quantization for the damped harmonic oscillator using the Bateman lagrangian. In particular, we prove that no square integrable vacuum exists for the natural ladder operators of the system, and that the only vacua can be found as distributions. This implies that the procedure proposed by some authors is only formally correct, and requires a much deeper analysis to be made rigorous. (Source: Physics Letters A)Physics Letters AjournalsSat, 15 Jun 2019 17:06:26 +0100703176248Interpreting weak value amplification with a toy realist model
https://medworm.com/703176247/interpreting-weak-value-amplification-with-a-toy-realist-model/
Publication date: Available online 14 June 2019Source: Physics Letters AAuthor(s): Josiah Sinclair, David Spierings, Aharon Brodutch, Aephraim M. SteinbergAbstractConstructing an ontology for quantum theory is challenging, in part due to measurement back-action. The Aharonov-Albert-Vaidman weak measurement formalism provides a method to predict measurement results (weak values) when back-action is negligible. The weak value appears analogous to a classical conditional mean, yet can be complex and unbounded. We study weak values in the context of a recent quantum optical experiment involving two-photon interactions. The results of the experiment are reinterpreted within a realist ‘stochastic optics’ model of light. We show that the conditional means of the intensities in the model corre...Physics Letters AjournalsSat, 15 Jun 2019 17:06:26 +0100703176247Controlling the stability and the electronic structure of transition metal dichalcogenide single layer under chemical doping
https://medworm.com/703176246/controlling-the-stability-and-the-electronic-structure-of-transition-metal-dichalcogenide-single-lay/
Publication date: Available online 14 June 2019Source: Physics Letters AAuthor(s): M. Debbichi, L. Debbichi, S. LebègueAbstractBy means of ab initio calculation based on density-functional theory (DFT), we have investigated the electronic and optical properties of single layer MoSe2 under chemical doping by various groups, such as -H, -OH, -NH2 and -CH3. This work is generalized for all polymorph 1H, 1T, 1T′ and the new investigated phase 1T″. We found that all those functional groups (FG) bonded covalently to the chalcogen atom (Se). The evaluation of adsorption energy shows that the hydrogen atom binds more strongly than other functional groups in particular with the T phase. Furthermore, the attachment of functional groups to T-MoSe2 leads to dramatic changes to the structure stabi...Physics Letters AjournalsSat, 15 Jun 2019 17:06:26 +0100703176246Efficient band structure engineering and visible-light response in ZrS2/GaS heterobilayer by electrical field or external strains
https://medworm.com/703176245/efficient-band-structure-engineering-and-visible-light-response-in-zrs2gas-heterobilayer-by-electri/
Publication date: Available online 14 June 2019Source: Physics Letters AAuthor(s): Yanxing Zhang, Zongxian YangAbstractVia first-principle methods, the electronic structures and optical properties of 2D ZrS2/GaS van der Waals heterostructure (vdWH) are studied. It is found that the band alignment changes from type-II to type-I under negative electrical field, and compressive strains. The transition points are -0.2 V/Å and -1%, respectively. The band gap changes efficiently under positive electrical field and compressive strains. The tensile strains increase the optical adsorption coefficients in ultraviolet regions, while the compressive strains increase the optical adsorption coefficients in visible region significantly. (Source: Physics Letters A)Physics Letters AjournalsSat, 15 Jun 2019 17:06:26 +0100703176245Study on the dynamic critical behavior of a ferroelectric heterostructure
https://medworm.com/703176244/study-on-the-dynamic-critical-behavior-of-a-ferroelectric-heterostructure/
Publication date: Available online 14 June 2019Source: Physics Letters AAuthor(s): Lian Cui, Chuanwen Chen, Yang XiangAbstractA Landau-Devonshire theory added in Landau–Khalatnikov dynamic equation has been used firstly to explore the dynamic critical behavior of a ferroelectric heterostructure composed of two different ferroelectric films. Two identical surface transition layers within each film are assumed, and an antiferroelectric interfacial coupling between two materials is considered. One interfacial parameter β is introduced to describe the differences of physical characteristics between two constituent films, which can reflect more realistic dynamic mechanism. It is found that the ferroelectric heterostructure may exhibit multi-loop hysteresis loop and four peaks of dielectric s...Physics Letters AjournalsSat, 15 Jun 2019 17:06:26 +0100703176244Band structure and cluster model calculations of LaNiO3 compared to photoemission, O 1s X-ray absorption, and optical absorption spectra
https://medworm.com/703176243/band-structure-and-cluster-model-calculations-of-lanio3-compared-to-photoemission-o-1s-x-ray-absorp/
We present results for the density of states (DOS), the spectral weight, and the dielectric function ε2. The calculations are compared to previous photoemission (PES), O 1s X-ray absorption (XAS), as well as optical absorption spectra. Both band structure and cluster model results are in good agreement with the experimental data. We point out that this concordance is very rare and far from trivial; we argue that this may be due to the unusual characteristics of the ground state of LaNiO3.Graphical abstract (Source: Physics Letters A)Physics Letters AjournalsSat, 15 Jun 2019 17:06:26 +0100703176243Persistent currents and induced magnetization in presence of external magnetic field and transition probabilities in presence of combined laser pulse and external magnetic field for a confined hydrogen atom
https://medworm.com/702698774/persistent-currents-and-induced-magnetization-in-presence-of-external-magnetic-field-and-transition-/
Publication date: Available online 12 June 2019Source: Physics Letters AAuthor(s): Vinod Prasad, Shalini Lumb Talwar, Sonia Lumb, G. Lefkidis, W. HübnerAbstractIn this work we propose to study an atom confined in a potential which consists of a Hulthén potential plus a ring-shaped potential. The atom is further subjected to a spherical confinement. The time-independent Schrödinger equation (TISE) of the system is solved numerically. Exact energy levels are obtained. The persistent current and induced magnetic field of such a confined atom is evaluated. Finally, the atomic system in this potential and confinement is subjected to short electromagnetic pulses, which are shown to induce enormous currents. (Source: Physics Letters A)Physics Letters AjournalsThu, 13 Jun 2019 21:39:23 +0100702698774The deviation factor and divergences in quantum electrodynamics, concrete examples
https://medworm.com/702698773/the-deviation-factor-and-divergences-in-quantum-electrodynamics-concrete-examples/
Publication date: Available online 12 June 2019Source: Physics Letters AAuthor(s): Lev SakhnovichAbstractWe consider the divergences in quantum electrodynamics. Our approach is based on ideas from the theory of generalized wave operators. In particular, we use the concept of the deviation factor. The deviation factor characterizes the deviations of the initial and final waves from the free waves. The approach is demonstrated on important examples. (Source: Physics Letters A)Physics Letters AjournalsThu, 13 Jun 2019 21:39:23 +0100702698773Manipulating electronic and magnetic properties of black phosphorene with 4d series transition metal adsorption
https://medworm.com/702698772/manipulating-electronic-and-magnetic-properties-of-black-phosphorene-with-4d-series-transition-metal/
Publication date: Available online 12 June 2019Source: Physics Letters AAuthor(s): Yusheng Wang, Nahong Song, Na Dong, Shijun Luo, Min Jia, Kai Xu, Yafeng Zheng, Hong Ling, Meng LiAbstractWe carry out first-principles calculations within density-functional theory to investigate the structural, electronic and magnetic properties of 4d transition metal (TM) decorated monolayer black phosphorene (BP). The results indicate that the TM adsorption on BP can have dilute magnetic semiconductor (DMS) properties. The spin polarized semiconducting state is realized in BP by adsorption of Y, Nb and Ru, while a half-metal state is obtained by Tc adsorption. In the case of two same types of TMs adsorption on BP, only 2Nb-s@BP shows DMS state. In particular, two different types of TMs decorated BP can in...Physics Letters AjournalsThu, 13 Jun 2019 21:39:23 +0100702698772Unstable twisted modes in interpenetrating space plasmas containing superthermal species
https://medworm.com/702378157/unstable-twisted-modes-in-interpenetrating-space-plasmas-containing-superthermal-species/
Publication date: Available online 11 June 2019Source: Physics Letters AAuthor(s): S. Bukhari, S.A. Khan, S. AliAbstractThe electrostatic twisted modes with orbital angular momentum and associated kinetic instability are studied in a permeating space plasma containing streaming particle species. The plasma containing superthermal electrons and ions is modeled by using a non-gyrotropic Kappa distribution function which penetrates through a relatively slow moving (static) plasma and gives rise to dispersion, damping and growth of ion-acoustic mode under various conditions. Using the Vlasov-Poisson model, the solutions of twisted modes are defined by Laguerre-Gaussian mode functions, which decompose the plasma distribution function and electric field into components characterized by the axial...Physics Letters AjournalsWed, 12 Jun 2019 17:09:24 +0100702378157Optoelectronic properties of two-dimensional GaN adsorbed with H, N and O: A first-principle study
https://medworm.com/702378156/optoelectronic-properties-of-two-dimensional-gan-adsorbed-with-h-n-and-o-a-first-principle-study/
Publication date: Available online 11 June 2019Source: Physics Letters AAuthor(s): Jian Tian, Lei Liu, Sihao Xia, Yu Diao, Feifei LuAbstractIn this paper, we have investigated optoelectronic properties of two-dimensional GaN adsorbed with non-metal atoms: H, N and O based on first-principle. We find that adsorption of H, N and O atom on 2D GaN is achieved by chemisorption, and the most stable adsorption site is at the top of N atom. Band structure of 2D GaN after adsorbing H atom moves to low energy region and two-dimensional GaN is transformed into an n-type semiconductor. After adsorption of N atom, a new impurity energy appears at the Fermi level, and N adatom could induce magnetism into 2D GaN. Static dielectric constants of 2D GaN increase and adsorption spectrums have extend to infra...Physics Letters AjournalsWed, 12 Jun 2019 17:09:24 +0100702378156Two-dimensional vector solitons in a cold atomic gas via electromagnetically induced transparency
https://medworm.com/702378155/two-dimensional-vector-solitons-in-a-cold-atomic-gas-via-electromagnetically-induced-transparency/
Publication date: Available online 11 June 2019Source: Physics Letters AAuthor(s): Wen-Wu Deng, Shun-Fang Chen, Ya-Wei Guo, Hong Li, Si-Liu Xu, Qi Guo, Milivoj J. Belić, Yuan ZhaoAbstractWe investigate the formation and propagation of vector vortex solitons (VSs) and unipolar solitons (USs) in a cold coherent atomic gas with a Bessel lattice (BL). The system considered is a gas with a tripod level configuration. Owing to the big enhancement of Kerr nonlinearity contributed by the electromagnetically induced transparency (EIT), a weak vector vortex soliton can be effectively formed with ultraslow propagation velocity. We also demonstrate that the characteristics of two-dimensional VSs and USs can be controlled and manipulated by adjusting the parameters of BL. Results obtained may be usefu...Physics Letters AjournalsWed, 12 Jun 2019 17:09:24 +0100702378155Multi-velocity and multi-temperature model of the mixture of polyatomic gases issuing from kinetic theory
https://medworm.com/702378154/multi-velocity-and-multi-temperature-model-of-the-mixture-of-polyatomic-gases-issuing-from-kinetic-t/
Publication date: Available online 11 June 2019Source: Physics Letters AAuthor(s): Milana Pavić-ČolićAbstractIn this paper, we consider Euler-like balance laws for mixture components that involve macroscopic velocities and temperatures for each different species. These laws are not conservation laws due to mutual interaction between species. In particular, source terms that describe the rate of change of momentum and energy of the constituents appear. These source terms are computed with the help of kinetic theory for mixtures of polyatomic gases. Moreover, if we restrict the attention to processes which occur in the neighborhood of the average velocity and temperature of the mixture, the phenomenological coefficients of extended thermodynamics can be determined from the computed source...Physics Letters AjournalsWed, 12 Jun 2019 17:09:24 +0100702378154Role of pulse shaping in control of focus and intensity of terahertz radiation
https://medworm.com/702059728/role-of-pulse-shaping-in-control-of-focus-and-intensity-of-terahertz-radiation/
Publication date: Available online 10 June 2019Source: Physics Letters AAuthor(s): Reenu Gill, Hitendra K. MalikAbstractIn this work, we uncover the role of lasers pulse shaping for controlling the terahertz peaks with their separation in addition to their intensities. We have developed a mathematical model for obtaining the amplitude, frequency, and power of the emitted Terahertz radiation for the lasers whose shape is tailored based on the index and skew parameter. Then the results are compared with the case of Gaussian laser pulse in collisional plasma. We optimize the process by applying magnetic field and by varying the index of the lasers for compensating the negative influence of collisions on the THz emission. Specifically the effect of laser beam width, magnetic field and collisio...Physics Letters AjournalsTue, 11 Jun 2019 12:39:25 +0100702059728Strain tuned electronic and magnetic anisotropy in SrTiO3 (110) surface
https://medworm.com/701268855/strain-tuned-electronic-and-magnetic-anisotropy-in-srtio3-110-surface/
Publication date: Available online 4 June 2019Source: Physics Letters AAuthor(s): Yan-ling Du, Hong-xia Bu, Zhi-yong Kong, Hui Sheng, Xue-jin Wang, Xiao-nan FangAbstractIn this work, the density functional theory (DFT) calculations are employed to investigate the effect of in-plane strain on the electronic and magnetic anisotropy of SrTiO-terminated SrTiO3 (110) surface. The two-dimensional electron gas (2DEG) at the surface comes from the surface Ti 3d orbitals and exhibits anisotropic transport properties. The ordering of the lowest conduction band states can be tuned by in-plane strain. In addition, the in-plane strain can effectively modify and reduce the electron effective mass of the SrTiO3 (110) surface, and the effect of the in-plane strain on the two directions of [001] and [11¯0...Physics Letters AjournalsSat, 08 Jun 2019 13:39:27 +0100701268855Energy behavior of spin electron cyclotron wave in a spin polarized plasma
https://medworm.com/701110058/energy-behavior-of-spin-electron-cyclotron-wave-in-a-spin-polarized-plasma/
This study may find its applications to understand the energy behavior inspin polarized solid state plasmas (Source: Physics Letters A)Physics Letters AjournalsFri, 07 Jun 2019 23:39:29 +0100701110058Waves in plasma formed by above-threshold ionization of gas atoms
https://medworm.com/701110057/waves-in-plasma-formed-by-above-threshold-ionization-of-gas-atoms/
Publication date: Available online 6 June 2019Source: Physics Letters AAuthor(s): K.Yu. Vagin, T.V. Mamontova, S.A. UryupinAbstractIn the regime of above-threshold ionization of gas atom in the field of laser radiation, plasma with photoelectron distribution consisting of peaks at discrete energy values is formed. It is shown that the number of longitudinal waves in such plasma coincides with the number of peaks in the distribution function. When peaks practically don't overlap, the dispersion law of each wave in the region of short waves is determined by electrons from the corresponding peak. In this case the phase and group velocities of the waves are close to the electron velocity, which corresponds to the peak maximum. It is possible to talk about such waves as an electronic sound, sin...Physics Letters AjournalsFri, 07 Jun 2019 23:39:29 +0100701110057Magnetized vector solitons in a spin-orbit coupled spin-1 Bose-Einstein condensate with Zeeman coupling
https://medworm.com/701110056/magnetized-vector-solitons-in-a-spin-orbit-coupled-spin-1-bose-einstein-condensate-with-zeeman-coupl/
Publication date: Available online 6 June 2019Source: Physics Letters AAuthor(s): Ping Peng, Guan-Qiang Li, Li-Chen Zhao, Wen-Li Yang, Zhan-Ying YangAbstractThe property of matter-wave vector solitons in a spin-1 Bose-Einstein condensate with spin-orbit and Zeeman couplings is investigated by multiscale perturbation method. The excitation spectrum and the corresponding state vectors of the system are obtained analytically, and they can be adjusted by the parameters of the system. The bright and dark vector solitons are formulated by reducing the three-component coupled Gross-Pitaeviskii equations to a standard nonlinear Schrödinger equatoin, which has the solutions of the bright and dark solitons with positive or negative mass depending on the product of the effective dispersive and nonli...Physics Letters AjournalsFri, 07 Jun 2019 23:39:29 +0100701110056Editors
https://medworm.com/701110036/editors/
Publication date: 8 August 2019Source: Physics Letters A, Volume 383, Issue 22Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 07 Jun 2019 23:39:29 +0100701110036A molecular dynamics study of the mechanical properties of h-BCN monolayer using a modified Tersoff interatomic potential
https://medworm.com/700793871/a-molecular-dynamics-study-of-the-mechanical-properties-of-h-bcn-monolayer-using-a-modified-tersoff-/
Publication date: Available online 5 June 2019Source: Physics Letters AAuthor(s): Ying-Yan Zhang, Qing-Xiang Pei, Zhen-Dong Sha, Yong-Wei ZhangAbstractUsing molecular dynamics (MD) simulations, we investigate the mechanical properties of hexagonal BCN monolayer, a newly synthesized two-dimensional material with an atom ratio of B/C/N = 1:1:1. The Tersoff potential is modified to get good agreement between predicted and measured fracture strengths of graphene. With this modified Tersoff potential, we perform extensive MD simulations to study the effect of temperature, strain rate and vacancy defect on the mechanical properties of h-BCN. It is found that h-BCN is a strong material with fracture strength of 81.4–93.5 GPa, albeit ∼35% lower than that of graphene. Similar to graphene, t...Physics Letters AjournalsThu, 06 Jun 2019 19:09:23 +0100700793871First-principle studies of the magnetism and optical properties of (Sc, Y)-codoped anatase TiO2 (101) surface
https://medworm.com/700793870/first-principle-studies-of-the-magnetism-and-optical-properties-of-sc-y-codoped-anatase-tio2-101/
Publication date: Available online 5 June 2019Source: Physics Letters AAuthor(s): Dongxiang Li, Ruiqin Li, Xinmao Qin, Wanjun YanAbstractWe calculated the electronic structure, magnetism and optical properties of the Sc-doped, Y-doped, and (Sc, Y)-codoped anatase TiO2 (101) surface using a projector augmented wave (PAW) method with GGA + U approximation. Sixteen doping systems were considered in the present work. The lattice distortion results in the generation of an internal local electric field. In addition, the difference between positive and negative spin charge densities leads to the generation of magnetism. With the exception of the Sc@in2 system, the width of band gap of the other doping systems increases to varying degrees, leading to a blueshift of the absorption edge. T...Physics Letters AjournalsThu, 06 Jun 2019 19:09:23 +0100700793870Bragg-induced oscillations in non-PT complex photonic lattices
https://medworm.com/700477075/bragg-induced-oscillations-in-non-pt-complex-photonic-lattices/
Publication date: Available online 4 June 2019Source: Physics Letters AAuthor(s): P.A. Brandão, S.B. CavalcantiAbstractWe investigate Bragg-induced oscillations in complex non-PT periodic structures, that is, a periodic medium with gain and loss and not necessarily symmetric under the combined action of parity and time reversal operations. We compare our analytic results based on the expansion of the optical field in Bragg-resonant plane waves with a direct numerical integration of the paraxial wave equation beyond the shallow potential approximation and using a wide Gaussian beam as initial condition. In particular, we study under which conditions a mode trapping phenomenon may still be observed and to inspect how the energy exchange between the spectral modes takes place during propagat...Physics Letters AjournalsWed, 05 Jun 2019 14:39:45 +0100700477075Elastic waves propagation in thin plate metamaterials and evidence of low frequency pseudo and local resonance bandgaps
https://medworm.com/700319271/elastic-waves-propagation-in-thin-plate-metamaterials-and-evidence-of-low-frequency-pseudo-and-local/
Publication date: Available online 3 June 2019Source: Physics Letters AAuthor(s): Muhammad, C.W. LimAbstractA comprehensive numerical simulation study on elastic wave propagation for a novel engineered thin plate metamaterial structural system is presented. To enhance the accuracy of model, a mesh convergence study is validated. The wave dispersion spectra with bandgaps for three types of structures are presented. Based on local resonance phenomena, the low frequency pseudo and local resonance bandgaps are reported. Highlights are also included for the Bragg scattering induced directional bandgaps. The effects of material and geometric parameters on bandgaps are discussed. The finite element based frequency response study further validates the reported bandgaps. The conclusions provide a n...Physics Letters AjournalsWed, 05 Jun 2019 00:15:46 +0100700319271Predicting mode-dependent phonon thermal conductivity of silicon nanoparticle using Boltzmann transport equation
https://medworm.com/700319270/predicting-mode-dependent-phonon-thermal-conductivity-of-silicon-nanoparticle-using-boltzmann-transp/
In conclusion, the letter infers the importance of mode dependent thermal conduction in silicon nanoparticle at elevated temperatures. (Source: Physics Letters A)Physics Letters AjournalsWed, 05 Jun 2019 00:15:46 +0100700319270Spin-dependent transport in four-terminal rings in the presence of the Rashba spin-orbit coupling
https://medworm.com/700319269/spin-dependent-transport-in-four-terminal-rings-in-the-presence-of-the-rashba-spin-orbit-coupling/
Publication date: Available online 4 June 2019Source: Physics Letters AAuthor(s): Li-Xue Zhai, Zhong AnAbstractSpin dependent transport in one-dimensional four-terminal rings (FTRs) is investigated in the presence of the Rashba spin-orbit coupling (RSOC). In the absence of the RSOC, the conductances as a function of the electron wave vector show resonant behavior for symmetrical configurations. For asymmetrical configurations, the conductances show peculiar zero-conductance resonances, and two kinds of conductance zeros have been found. In the presence of the RSOC, the original conductance zeros disappear as new conductance zeros are generated. Moreover, two kinds of symmetry relations have been found in the conductances, the spin dependent conductances and the spin polarizations. For the ...Physics Letters AjournalsWed, 05 Jun 2019 00:15:46 +0100700319269Strain tuned electronic and magnetic anisotropy in SrTiO3(110) surface
https://medworm.com/700319268/strain-tuned-electronic-and-magnetic-anisotropy-in-srtio3110-surface/
Publication date: Available online 4 June 2019Source: Physics Letters AAuthor(s): Yan-ling Du, Hong-xia Bu, Zhi-yong Kong, Hui Sheng, Xue-jin Wang, Xiao-nan FangAbstractIn this work, the density functional theory (DFT) calculations are employed to investigate the effect of in-plane strain on the electronic and magnetic anisotropy of SrTiO-terminated SrTiO3 (110) surface. The two-dimensional electron gas (2DEG) at the surface comes from the surface Ti 3d orbitals and exhibits anisotropic transport properties. The ordering of the lowest conduction band states can be tuned by in-plane strain. In addition, the in-plane strain can effectively modify and reduce the electron effective mass of the SrTiO3 (110) surface, and the effect of the in-plane strain on the two directions of [001] and [11¯0...Physics Letters AjournalsWed, 05 Jun 2019 00:15:46 +0100700319268Nonlinear quantum mechanics in a q-deformed Hilbert space
https://medworm.com/700319267/nonlinear-quantum-mechanics-in-a-q-deformed-hilbert-space/
Publication date: Available online 4 June 2019Source: Physics Letters AAuthor(s): Bruno G. da Costa, Ernesto P. BorgesAbstractWe introduce a generalized temporal evolution operator that belongs to a q-deformed Hilbert space. This q-unitary operator is used to revisit a nonlinear form of the Schrödinger equation related to the nonextensive thermostatistical framework through a q-deformed Dirac formalism. We also obtain generalized versions of the density matrix operator, the Liouville-von Neumann equation and the Bloch vector, that can be used in the description of decoherence phenomena. Deformed rotation matrices are used for the problem of the spin 12 precession in a uniform magnetic field. (Source: Physics Letters A)Physics Letters AjournalsWed, 05 Jun 2019 00:15:46 +0100700319267Editors
https://medworm.com/700319250/editors/
Publication date: 29 July 2019Source: Physics Letters A, Volume 383, Issue 21Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 05 Jun 2019 00:15:46 +0100700319250Comprehensive calculations and prominent thermoelectric properties of Li3P and Li3As
https://medworm.com/699536680/comprehensive-calculations-and-prominent-thermoelectric-properties-of-li3p-and-li3as/
Publication date: Available online 31 May 2019Source: Physics Letters AAuthor(s): Qi Zhong, Zhenhong Dai, Jianye Liu, Yinchang Zhao, Sheng MengAbstractBased on first-principles calculations, together with the Boltzmann transport equation and semiclassical analysis, we carried out a series of studies on the thermoelectric properties of Li3P and Li3As, such as the thermal conductivity κ which contains lattice thermal conductivity κL and electronic thermal conductivity κe, electron structure, Seebeck coefficient S and electrical conductivity σ, and obtained extremely large Seebeck coefficient S and extraordinary low lattice conductivity κL which are 2.832 W m−1 K−1 and 2.795 W m−1 K−1 at a temperature of 300 K for Li3P and Li3As, respectively. Benefited from t...Physics Letters AjournalsSun, 02 Jun 2019 00:15:34 +0100699536680Absorbance and optical responsivity of two-dimensional mechanical resonators at oblique incidence
https://medworm.com/699536679/absorbance-and-optical-responsivity-of-two-dimensional-mechanical-resonators-at-oblique-incidence/
Publication date: Available online 31 May 2019Source: Physics Letters AAuthor(s): Wenjing Mao, Chen Yang, Heng Lu, Jun Lu, Lin Wan, Fengnan Chen, Ying Yan, Joel MoserAbstractOptical reflectometry is a well known technique employed to measure the displacement response of mechanical resonators. This technique consists in shining monochromatic light on the resonator at normal incidence and measuring the intensity of reflected light. In the case of resonators fabricated from suspended membranes of two-dimensional materials, fluctuations of distance between the membrane and the underlying substrate are transduced into fluctuations of reflected light intensity. Here we consider an alternate configuration where we shine light at oblique incidence. Within the plane wave model, we calculate the abs...Physics Letters AjournalsSun, 02 Jun 2019 00:15:34 +0100699536679A superhard orthorhombic carbon with all six-membered-ring in sp3 bonding networks
https://medworm.com/699536677/a-superhard-orthorhombic-carbon-with-all-six-membered-ring-in-sp3-bonding-networks/
Publication date: Available online 31 May 2019Source: Physics Letters AAuthor(s): Kun Bu, Jian-Tao Wang, Zhen-Zhen Li, Hiroshi Mizuseki, Yoshiyuki KawazoeAbstractWe identify by first-principles calculations a new diamond-like carbon phase with a 16-atom orthorhombic primitive cell in Pbcn (D2h14) symmetry. This new carbon allotrope consists of all sp3 six-membered rings like as the reported BC8, BC12 and R16 carbon, while energetically more stable than these carbon phases. Its dynamical stability has been confirmed by phonon mode analysis and molecular dynamics simulations. The calculated bulk modulus (435 GPa) and Vickers hardness (93 GPa) are comparable to that of diamond, showing as a superhard carbon material. Electronic band calculations reveal that it is an insulator with an indirect...Physics Letters AjournalsSun, 02 Jun 2019 00:15:34 +0100699536677Ultra-wideband water-based metamaterial absorber with temperature insensitivity
https://medworm.com/699536676/ultra-wideband-water-based-metamaterial-absorber-with-temperature-insensitivity/
Publication date: Available online 31 May 2019Source: Physics Letters AAuthor(s): Yanfei Zhou, Zhaoyang Shen, Xiaojun Huang, Jiong Wu, Yujun Li, Siqi Huang, Helin YangAbstractThe natural water has frequency dispersion and its permittivity is also related to temperature, which are important factors to design temperature insensitive absorber at microwave frequency. Here, a water-based metamaterial absorber which is fabricated by 3D-printing is proposed. The absorber can perform stably at different temperatures and it also shows 90% absorption in the frequency range of 7.9–21.7 GHz. The experiment proves that the absorber can work at a wide incident angle and is polarization insensitive. Based on these features, the water-based absorber could be applied to various electromagnetic scenarios ...Physics Letters AjournalsSun, 02 Jun 2019 00:15:34 +0100699536676Positivity and complete positivity of differentiable quantum processes
https://medworm.com/699223986/positivity-and-complete-positivity-of-differentiable-quantum-processes/
Publication date: Available online 31 May 2019Source: Physics Letters AAuthor(s): Gustavo Montes Cabrera, David Davalos, Thomas GorinAbstractWe study quantum processes, as one parameter families of differentiable completely positive and trace preserving (CPTP) maps. Using different representations of the generator, and the Sylvester criterion for positive semi-definite matrices, we obtain conditions for the divisibility of the process into completely positive (CP-divisibility) and positive (P-divisibility) infinitesimal maps. Both concepts are directly related to the definition of quantum non-Markovianity. For the single qubit case we show that CP- and P-divisibility only depend on the dissipation matrix in the master equation form of the generator. We then discuss three classes of process...Physics Letters AjournalsFri, 31 May 2019 20:12:25 +0100699223986Novel effect induced by spacetime curvature in quantum hydrodynamics
https://medworm.com/698911908/novel-effect-induced-by-spacetime-curvature-in-quantum-hydrodynamics/
Publication date: Available online 29 May 2019Source: Physics Letters AAuthor(s): T. Koide, T. KodamaAbstractThe interplay between quantum fluctuation and spacetime curvature is shown to induce an additional quantum-curvature (QC) term in the energy-momentum tensor of fluid using the generalized framework of the stochastic variational method (SVM). The QC term is necessary to satisfy the momentum conservation but the corresponding quantum hydrodynamics is not necessarily cast into the form of the Schrödinger equation, differently from the case of the Euclidean spacetime. This seems to suggest that the existence of the Hilbert space is not a priori requirement in the quantization of curved spacetime systems. As an example of curved spacetime systems, we apply the Friedmann-Robertson-Walker...Physics Letters AjournalsThu, 30 May 2019 15:36:32 +0100698911908Phase transition in the one-dimensional pair-hopping model with unusual one-electron hopping
https://medworm.com/698911907/phase-transition-in-the-one-dimensional-pair-hopping-model-with-unusual-one-electron-hopping/
Publication date: Available online 29 May 2019Source: Physics Letters AAuthor(s): Hanqin Ding, Jun ZhangAbstractBy modifying the conventional one-electron hopping behavior, we study effects of an occupation-dependent hopping on the ground state of the half-filled one-dimensional pair-hopping model. At weak coupling, the use of bosonization and renormalization-group analysis techniques helps to derive the phase diagram. Such unusual hopping is shown to drive a spin-gap transition and to introduce a new region where the triplet superconducting instability dominates for positively small pair-hopping interaction. (Source: Physics Letters A)Physics Letters AjournalsThu, 30 May 2019 15:36:32 +0100698911907Zone folding induced tunable topological interface states in one-dimensional phononic crystal plates
https://medworm.com/698911906/zone-folding-induced-tunable-topological-interface-states-in-one-dimensional-phononic-crystal-plates/
Publication date: Available online 29 May 2019Source: Physics Letters AAuthor(s): Hongbo Zhang, Bilong Liu, Xilong Zhang, Qianqian Wu, Xingang WangAbstractIn previous literature, the realization of topological interface state in one-dimensional periodic system is strongly relied on the tedious parameter adjustment to search for the Dirac cone. In this paper, based on a strategy of zone folding, multiple topological interface modes for the shear horizontal guided waves in one dimensional phononic crystal plate are investigated by using finite element method and eigenmode matching theory, in which the Dirac points are formed by simply making the unit cell double. Significantly, by simply contracting or expanding the stubs can bring the topological phase transition. Furthermore, the topologic...Physics Letters AjournalsThu, 30 May 2019 15:36:32 +0100698911906Enhanced gas sensing performance of polyaniline incorporated with graphene: A first-principles study
https://medworm.com/698911905/enhanced-gas-sensing-performance-of-polyaniline-incorporated-with-graphene-a-first-principles-study/
Publication date: Available online 29 May 2019Source: Physics Letters AAuthor(s): Zhi Guo, Ningbo Liao, Miao Zhang, Aixin FengAbstractConducting polymers such as polyaniline (PANI) are potential sensing materials for ammonia due to their fast response and low cost, however, the corresponding sensing mechanism needs to be studied further. In this paper, molecular dynamic and first-principles simulations are carried out to investigate ammonia sensing mechanisms of polyaniline/graphene heterostructure. The adsorption of ammonia at different locations of pure polyaniline and graphene/PANI composites is analyzed. The band gap for graphene/PANI system shows more significant change after adsorption than that of pure polyaniline, which indicates higher sensitivity for detecting ammonia, and the re...Physics Letters AjournalsThu, 30 May 2019 15:36:32 +0100698911905Time travel without paradoxes: Ring resonator as a universal paradigm for looped quantum evolutions
https://medworm.com/698911904/time-travel-without-paradoxes-ring-resonator-as-a-universal-paradigm-for-looped-quantum-evolutions/
Publication date: Available online 29 May 2019Source: Physics Letters AAuthor(s): Marek CzachorAbstractA ring resonator involves a scattering process where a part of the output is fed again into the input. The same formal structure is encountered in the problem of time travel in a neighborhood of a closed timelike curve (CTC). We know how to describe quantum optics of ring resonators, and the resulting description agrees with experiment. We can apply the same formal strategy to any looped quantum evolution, in particular to the time travel. The argument is in its essence a topological one and thus does not refer to any concrete geometry. It is shown that the resulting paradigm automatically removes logical inconsistencies associated with chronology protection, provided all input-output rel...Physics Letters AjournalsThu, 30 May 2019 15:36:32 +0100698911904Quantumness of ensembles via coherence
https://medworm.com/698756534/quantumness-of-ensembles-via-coherence/
Publication date: Available online 28 May 2019Source: Physics Letters AAuthor(s): Yuanyuan Mao, Hongting SongAbstractThe notion of quantum ensembles is necessary for a description of quantum systems with incomplete information, which often occurs in the theory of quantum measurement and communication. Since ensembles involving non-commuting states possess intrinsic quantumness and play a central role in various quantum information processing tasks, it is desirable to quantify the quantum characteristics in ensembles from different points of view. In this paper, we define a quantifier for quantumness of quantum ensembles from the perspective of coherence, and prove this quantifier satisfies almost all natural desiderata for a measure of quantumness recently suggested by Li et al. (2017) [12...Physics Letters AjournalsThu, 30 May 2019 01:06:38 +0100698756534Generalized Cornu-type spirals and their Darboux parametric deformations
https://medworm.com/698756533/generalized-cornu-type-spirals-and-their-darboux-parametric-deformations/
Publication date: Available online 28 May 2019Source: Physics Letters AAuthor(s): Haret C. Rosu, Stefan C. Mancas, Chun-Chung HsiehAbstractWe generalize the Fresnel integrals and introduce a class of planar spirals Fn, which contains the Cornu spiral as the case F2. Their Darboux parametric deformations are also investigated. The F3 spiral and some of its Darboux deformed counterparts are graphically illustrated. (Source: Physics Letters A)Physics Letters AjournalsThu, 30 May 2019 01:06:38 +0100698756533Magnetotransport through ac driven ferromagnetic graphene nanoribbons
https://medworm.com/698756532/magnetotransport-through-ac-driven-ferromagnetic-graphene-nanoribbons/
We present a theoretical study on the spin-dependent transport through the ferromagnetic graphene nanoribbons in the presence of a magnetic and an in-plane ac electric field, and find that when the ac field is applied, in the two-terminal ferromagnetic graphene device, for the parallel configurations of the electrodes' magnetizations, the width of the even-number conductance plateaus decrease, the new conductance plateaus appear at the odd-number positions, and the even-number conductance plateaus at the high energy are quenched under the sufficiently strong ac field. In contrast, for the antiparallel configuration of the electrodes' magnetizations, the odd-plateaus of the conductance shrink, and the new plateaus developed at the even-number positions. The magnetic resistance exhibits a su...Physics Letters AjournalsThu, 30 May 2019 01:06:38 +0100698756532Editors
https://medworm.com/698756510/editors/
Publication date: 18 July 2019Source: Physics Letters A, Volume 383, Issue 20Author(s): (Source: Physics Letters A)Physics Letters AjournalsThu, 30 May 2019 01:06:38 +0100698756510Experimental determination of interfacial energy for solid Al in the Al-Sn-Mg eutectic system with Bridgman-type apparatus
https://medworm.com/697359837/experimental-determination-of-interfacial-energy-for-solid-al-in-the-al-sn-mg-eutectic-system-with-b/
Publication date: Available online 23 May 2019Source: Physics Letters AAuthor(s): Canan Alper Billur, Buket SaatçiAbstractThe equilibrated grain boundary groove shape of solid Al in equilibrium with Al-Sn-Mg eutectic liquid was observed by using a Bridgman type directional solidification apparatus. The ratio of the thermal conductivity of the equilibrated liquid to the thermal conductivity of solid Al has been obtained as 0.91. In addition, the average Gibbs-Thomson coefficient, Γ‾=(4.20±0.35)×10−8Km, the solid-liquid interfacial energy, σSL=180.68±23.48mJ/m2 and the grain boundary energy, σGB=309.30±29.47mJ/m2, in the Al/Al-Sn-Mg system have been calculated from the measured grain boundary shapes.Graphical abstract (Source: Physics Letters A)Physics Letters AjournalsFri, 24 May 2019 16:12:28 +0100697359837Editors
https://medworm.com/697359819/editors/
Publication date: 8 July 2019Source: Physics Letters A, Volume 383, Issue 19Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 24 May 2019 16:12:28 +0100697359819Magnetomechanical coupling enhancement via high-density nanoprecipitation in Co70Fe30 alloy
https://medworm.com/697206626/magnetomechanical-coupling-enhancement-via-high-density-nanoprecipitation-in-co70fe30-alloy/
Publication date: Available online 22 May 2019Source: Physics Letters AAuthor(s): Yalong Zhao, Jiheng Li, Xiaoqian Bao, Xing Mu, Xuexu GaoAbstractMagnetostrictive materials with high magnetomechanical coupling performance are required for transducer design and tunable resonator applications. The magnetostriction of Fe-Ga and Co-Fe alloy can be remarkably increased by high-density and semicoherent nanoparticles. In this work, we found that the magnetomechanical coupling of Co70Fe30 alloy can be obviously enhanced by high-density nanoprecipitation. This outstanding enhancement originates from the semicoherent face-centered tetragonal (fct) nanoparticles embedded in a body-centered cubic (bcc) matrix, which may promote magnetic domain rotations under applications of stress. The result indicat...Physics Letters AjournalsFri, 24 May 2019 02:06:31 +0100697206626Angular momentum of radiation from a charge in circular and spiral motion
https://medworm.com/697206625/angular-momentum-of-radiation-from-a-charge-in-circular-and-spiral-motion/
Publication date: Available online 22 May 2019Source: Physics Letters AAuthor(s): Vladimir Epp, Ulyana GuselnikovaAbstractWe study theoretically the vortex radiation of a relativistic charged particle. General expressions for the spectral and angular distributions of angular momentum of radiation are derived for an arbitrary moving charge. Special attention is given to calculation of the angular momentum of synchrotron radiation. We obtain the spectrum and the angular distribution of angular momentum carried by synchrotron radiation. Similar expressions for the angular momentum of radiation of a charge moving on a spiral trajectory are derived by use of Lorentz transformations. It is shown that the main part of angular momentum in this case is emitted at a small angle to the vortex axis. R...Physics Letters AjournalsFri, 24 May 2019 02:06:31 +0100697206625Glass transition in disordered clusters
https://medworm.com/697206624/glass-transition-in-disordered-clusters/
Publication date: Available online 22 May 2019Source: Physics Letters AAuthor(s): X.Y. Li, D.Y. Sun, X.G. GongAbstractUsing molecular dynamics simulations, the melting behavior of disordered aluminum clusters with 30∼100 atoms has been systematically studied. We find that, all the disordered clusters undergo a glass transition before completely melting. We identify two characteristic temperatures, i.e. Ts and Tg (the glass transition temperature). When the temperature is higher than Ts, the cluster shape starts to change, accordingly the configurational entropy emerges. For temperatures between Ts and Tg, the disordered clusters show a remarkable cooperative diffusion, more importantly, the activation energy of cooperative diffusions below Tg is always lower than that of the liquid state...Physics Letters AjournalsFri, 24 May 2019 02:06:31 +0100697206624Structural features and electronic properties of Group-IIIB pnictides nanosheets and nanoribbons
https://medworm.com/697206623/structural-features-and-electronic-properties-of-group-iiib-pnictides-nanosheets-and-nanoribbons/
Publication date: Available online 22 May 2019Source: Physics Letters AAuthor(s): Liu JianAbstractTwo-dimensional (2D) materials exhibit unique electronic properties compared with their bulks. A systematical study of new type 2D tetragonal materials of MPn (M = Sc and Y; Pn = P, As and Sb) nanosheets and the corresponding nanoribbons are proposed by density functional theory calculations. Several thermodynamically stable 2D tetragonal structures were firstly determined, and such novel tetragonal structures bilayer MPn(100) exhibit extraordinary Weyl semimetal electronic structures, while monolayer MPn(110) are semiconductors. Moreover, bilayer MPn(100) nanoribbons with zigzag edges show metallic behavior, whereas those with linear edges show semiconducting properties. The band gaps for bil...Physics Letters AjournalsFri, 24 May 2019 02:06:31 +0100697206623Effects of Zr and V additions on the stability and migration of He in bcc W: A first-principles study
https://medworm.com/697206622/effects-of-zr-and-v-additions-on-the-stability-and-migration-of-he-in-bcc-w-a-first-principles-stud/
Publication date: Available online 22 May 2019Source: Physics Letters AAuthor(s): Ningning Zhang, Yujuan Zhang, Yu Yang, Ping Zhang, Changchun GeAbstractThe effects of zirconium (Zr) and vanadium (V) on the dissolution, diffusion and trapping behaviors of helium (He) in body-centered cubic (bcc) tungsten (W) have been investigated using first-principles simulations. We found that Zr and V atoms usually prefer to disperse into W-rich region rather than aggregate in W host lattice. Energetically, the relatively stable position for an interstitial He remains the tetrahedral interstitial site in W with the presence of Zr/V atom. The solution energy of the He atom is reduced because of the attractive interaction between He and Zr/V atom. Compared to W with Zr, the stronger attractive interactio...Physics Letters AjournalsFri, 24 May 2019 02:06:31 +0100697206622Evaluating the robustness of rogue waves under perturbations
https://medworm.com/696897961/evaluating-the-robustness-of-rogue-waves-under-perturbations/
Publication date: Available online 21 May 2019Source: Physics Letters AAuthor(s): C.B. Ward, P.G. Kevrekidis, N. WhitakerAbstractRogue waves, and their periodic counterparts, have been shown to exist in a number of integrable models. However, relatively little is known about the existence of these objects in models where an exact formula is unattainable. In this work, we develop a novel numerical perspective towards identifying such states as localized solutions in space-time. Importantly, we illustrate this methodology for different perturbations of nonlinear Schrödinger models. In particular, in addition to benchmarking known solutions (and confirming their numerical propagation under controllable error) enables the continuation of such solutions over parametric variations to non-integr...Physics Letters AjournalsWed, 22 May 2019 21:12:24 +0100696897961Topological states at exceptional points
https://medworm.com/696897960/topological-states-at-exceptional-points/
Publication date: Available online 21 May 2019Source: Physics Letters AAuthor(s): C. YuceAbstractWe consider an N-level non-Hermitian Hamiltonian with an exceptional point of order N. We define adiabatic equivalence in such systems and explore topological phase. We show that the topological exceptional states appear at the interface of topologically distinct systems. We discuss that topological states appear even in closed systems. We explore dynamical robustness of exceptional edge states. (Source: Physics Letters A)Physics Letters AjournalsWed, 22 May 2019 21:12:24 +0100696897960Resistivity of a 2d quantum critical metal
https://medworm.com/696897959/resistivity-of-a-2d-quantum-critical-metal/
Publication date: Available online 21 May 2019Source: Physics Letters AAuthor(s): Komal Kumari, Raman Sharma, Navinder SinghAbstractWe calculate resistivity in the paramagnetic phase just above the curie temperature in a 2d ferromagnetic metal. The required dynamical susceptibility in the formalism of resistivity is calculated within the Random Phase Approximation (RPA). The mechanism of resistivity is magnetic scattering, in which s-band electrons are scattered off the magnetic spin fluctuations of d-band electrons. We use the s-d Hamiltonian formalism. We find that near the quantum critical point the resistivity in 2d scales as T43 and in the high temperature limit resistivity scales as proportional to T. In contrast to it, resistivity due to phonon scattering is given by T5 in low tempe...Physics Letters AjournalsWed, 22 May 2019 21:12:24 +0100696897959The effective geometry Monte Carlo algorithm: Applications to molecular communication
https://medworm.com/696742119/the-effective-geometry-monte-carlo-algorithm-applications-to-molecular-communication/
Publication date: Available online 20 May 2019Source: Physics Letters AAuthor(s): Fatih Dinc, Leander Thiele, Bayram Cevdet AkdenizAbstractIn this work, we address the systematic biases and random errors stemming from finite step sizes encountered in diffusion simulations. We introduce the Effective Geometry Monte Carlo (EG-MC) simulation algorithm which modifies the geometry of the receiver. We motivate our approach in a 1D toy model and then apply our findings to a spherical absorbing receiver in a 3D unbounded environment. We show that with minimal computational cost the impulse response of this receiver can be precisely simulated using EG-MC. Afterwards, we demonstrate the accuracy of our simulations and give tight constraints on the single free parameter in EG-MC. Finally, we comment ...Physics Letters AjournalsWed, 22 May 2019 06:39:23 +0100696742119Electrical transport and thermoelectric properties of Te–Se solid solutions
https://medworm.com/696742118/electrical-transport-and-thermoelectric-properties-of-tese-solid-solutions/
Publication date: Available online 20 May 2019Source: Physics Letters AAuthor(s): Manman Yang, Hongyu Zhu, Wencai Yi, Shangsheng Li, Meihua Hu, Qiang Hu, Baoli Du, Xiaobing Liu, Taichao SuAbstractIn this paper, p-type thermoelectric material Te–Se solid solutions have been successfully prepared by the high-pressure technique. The thermal conductivity of Te was depressed sharply by Se alloying. An extremely low thermal conductivity ∼0.27 W m−1 K−1 was obtained for Te alloyed with 15 mol% Se, which near the theoretical minimum, κmin. The bipolar diffusion effect of Te was suppressed by Se alloying due to the increased band gap, which lead to enhanced Seebeck coefficient and depressed bipolar diffusion thermal conductivity under high temperature. The maximum figure of merit...Physics Letters AjournalsWed, 22 May 2019 06:39:23 +0100696742118Mean-field properties of impurity in Bose gas with three-body forces
https://medworm.com/695821914/mean-field-properties-of-impurity-in-bose-gas-with-three-body-forces/
Publication date: Available online 17 May 2019Source: Physics Letters AAuthor(s): Volodymyr PastukhovAbstractWe exactly analyze, on the mean-field level, the low-momentum properties of a single impurity atom loaded in the dilute one-dimensional Bose gas with two- and three-body short-range interactions. Particularly the Bose polaron binding energy and the quasiparticle residue are calculated for the considered system in the broad region of parameters change. We also explore the generic mean-field formula for the polaron effective mass which was shown to depend on the density profile of bath particles with a motionless impurity immersed. (Source: Physics Letters A)Physics Letters AjournalsSat, 18 May 2019 15:09:24 +0100695821914Thermodynamic properties of the XY ferrimagnetic spin-(1/2,1) chain with both longitudinal and transverse single-ion anisotropies
https://medworm.com/695821913/thermodynamic-properties-of-the-xy-ferrimagnetic-spin-121-chain-with-both-longitudinal-and-trans/
Publication date: Available online 17 May 2019Source: Physics Letters AAuthor(s): Xin Yang, Yuge Chen, Mengmeng Lu, Bin ChenAbstractWe investigate the finite temperature properties of the mixed spin-1/2 and spin-1 ferrimagnetic chain with both longitudinal single-ion anisotropy Dz and transverse single-ion anisotropy Dx. The spin excitation spectrum as well as the thermodynamic quantities are explored by means of the Villian transformation theory. We find two branches of the low-lying energy spectrum are strongly dependent on the model Hamiltonian parameters J1,J2, Dz,Dx. Our results agree well with the exact method results for the mixed spin-1/2 and spin-1 Ising chain. The thermodynamic quantities of XY ferrimagnetic spin-(1/2,1) chain varying with Dz and Dx, such as free energy, internal...Physics Letters AjournalsSat, 18 May 2019 15:09:24 +0100695821913Interlayer vibration of twisted bilayer graphene: A first-principles study
https://medworm.com/695821912/interlayer-vibration-of-twisted-bilayer-graphene-a-first-principles-study/
Publication date: Available online 17 May 2019Source: Physics Letters AAuthor(s): Hong-Quan Song, Zhao Liu, Dong-Bo ZhangAbstractMulti-layered structures of graphene and other two dimensional materials are novel organizations with fascinating properties. In this work, we investigate the interlayer lattice dynamics of the Moiré superlattice of twisted bilayer graphene (tBLG) using first-principles calculations. Due to the structural complexity, we calculate the frequencies of the interlayer breathing and shear vibrational modes of the tBLG without exploring all the degree of freedoms of the tBLG. Our calculation shows that the frequencies of breathing and shear modes display pronounced dependence on twisting angle, and compare well with the state of arts experimental measurements. We hint ...Physics Letters AjournalsSat, 18 May 2019 15:09:24 +0100695821912Phase modulation of acoustic vortex beam with metasurfaces
https://medworm.com/695821911/phase-modulation-of-acoustic-vortex-beam-with-metasurfaces/
We present a new acoustic metasurface structure to generate the stable acoustic vortex beams with controllable topological charge in the broadening of operating frequency. The proposed acoustic metasurface can dynamically achieve a full span of 360° phase modulation by three simple solutions. Acoustic plane beam and acoustic vortex beam can convert each other based on multi-metasurfaces combination. Potential applications of such phase modulation schemes can be anticipated. (Source: Physics Letters A)Physics Letters AjournalsSat, 18 May 2019 15:09:24 +0100695821911Absolute cross sections of ultra-soft x-ray radiation in electron scattering upon atoms and the soft-photons approximation
https://medworm.com/695664464/absolute-cross-sections-of-ultra-soft-x-ray-radiation-in-electron-scattering-upon-atoms-and-the-soft/
Publication date: Available online 10 May 2019Source: Physics Letters AAuthor(s): Aleksei S. Kornev, Boris A. Zon, Miron Ya. AmusiaAbstractWe calculated the cross sections of ultra-soft x-ray bremsstrahlung in electron scattering upon Ar, Kr and Xe. The results are consistent with the absolute values of the differential cross sections measured by Gnatchenko et al. (2009) [17] for scattering electrons with an energy of 600 eV on these atoms. (Source: Physics Letters A)Physics Letters AjournalsSat, 18 May 2019 00:39:25 +0100695664464A look at the generalized Darboux transformations for the quasinormal spectra in Schwarzschild black hole perturbation theory: Just how general should it be?
https://medworm.com/695664452/a-look-at-the-generalized-darboux-transformations-for-the-quasinormal-spectra-in-schwarzschild-black/
Publication date: Available online 16 May 2019Source: Physics Letters AAuthor(s): A.V. Yurov, V.A. YurovAbstractIn this article we take a close look at three types of transformations usable in the Schwarzschild black hole perturbation theory: a standard (DT), a binary (BDT) and a generalized (GDT) Darboux transformations. In particular, we discuss the absolutely crucial property of isospectrality of the aforementioned transformations which guarantees that the quasinormal mode (QNM) spectra of potentials, related via the transformation, completely coincide. We demonstrate that, while the first two types of the Darboux transformations (DT and BDT) are indeed isospectral, the situation is wildly different for the GDT: it violates the isospectrality requirement and is therefore only valid for ...Physics Letters AjournalsSat, 18 May 2019 00:39:25 +0100695664452Interference effect in the ionization loss of high-energy electron bunches
https://medworm.com/695664451/interference-effect-in-the-ionization-loss-of-high-energy-electron-bunches/
Publication date: Available online 16 May 2019Source: Physics Letters AAuthor(s): S.V. Trofymenko, N.F. Shul'gaAbstractThe ionization loss of high-energy electron bunches in ultrathin targets is considered. It is shown that the effect of coherent amplification of the ionization loss, analogous to such an effect in radiation, can take place for sufficiently small bunches with high particle densities. It is demonstrated that such an effect can manifest itself for bunch parameters achievable at modern accelerator facilities. (Source: Physics Letters A)Physics Letters AjournalsSat, 18 May 2019 00:39:25 +0100695664451Generation of stable multi-vortex clusters in a dissipative medium with anti-cubic nonlinearity
https://medworm.com/695349462/generation-of-stable-multi-vortex-clusters-in-a-dissipative-medium-with-anti-cubic-nonlinearity/
Publication date: Available online 16 May 2019Source: Physics Letters AAuthor(s): Yunli Qiu, Boris A. Malomed, Dumitru Mihalache, Xing Zhu, Jianle Peng, He YingjiAbstractWe demonstrate the generation of vortex solitons in a model of dissipative optical media with the singular anti-cubic (AC) nonlinearity, by launching a vorticity-carrying Gaussian input into the medium modeled by the cubic-quintic complex Ginzburg-Landau equation. The effect of the AC term on the beam propagation is investigated in detail. An analytical result is produced for the asymptotic form of fundamental and vortical solitons at the point of r→0, which is imposed by the AC term. Numerical simulations identify parameter domains that maintain stable dissipative solitons in the form of vortex clusters. The number of v...Physics Letters AjournalsThu, 16 May 2019 19:39:29 +0100695349462A first-principles study on the interaction of CO molecules with VIII transition metals-embedded graphitic carbon nitride as an excellent candidate for CO sensor
https://medworm.com/695036225/a-first-principles-study-on-the-interaction-of-co-molecules-with-viii-transition-metals-embedded-gra/
Publication date: Available online 14 May 2019Source: Physics Letters AAuthor(s): Hadi Basharnavaz, Aziz Habibi-Yangjeh, Seyed Hossein KamaliAbstractWe studied the adsorption behavior of CO molecules over graphitic carbon nitride (gCN) and VIII transition metals (TM)-embedded gCN systems (TM=Ni, Pd, and Pt atoms) using density functional theory. The results indicated that the Pt-embedded gCN is excellent candidate for adsorption of CO molecules with adsorption energy of −2.77 eV, which is much better than those of the other adsorbents. Furthermore, it was observed that the band gap energies of TM-embedded systems were less than that of pristine gCN and decoration of transition metal atoms leads to the formation of mid gap impurity states, resulting in increase of electrical conductivity....Physics Letters AjournalsWed, 15 May 2019 14:36:36 +0100695036225Acoustic crystals with Dirac-like cone dispersion mapped to effective zero-index acoustic materials
https://medworm.com/695036224/acoustic-crystals-with-dirac-like-cone-dispersion-mapped-to-effective-zero-index-acoustic-materials/
Publication date: Available online 14 May 2019Source: Physics Letters AAuthor(s): Jian-He Liang, Yuan-Wei Yao, Xin Zhang, Fu-Gen Wu, Hua-Feng Dong, Li-Xiang HanAbstractDifferent two-dimensional (2D) acoustic crystals are investigated and the conditions under which these acoustic crystals can be mapped to effective zero-index materials are discussed. Acoustic crystals with Dirac-like points can only be mapped to effective zero-index materials when all three of the following conditions are met simultaneously: (i) the Dirac-like point is formed by monopole and dipole moments, (ii) the Dirac-like point is at a low enough frequency, and (iii) in the extended states above the Dirac-like point frequency, there is only one propagating band. The difference between the optical and acoustic regime is...Physics Letters AjournalsWed, 15 May 2019 14:36:36 +0100695036224Tunable multi-band terahertz absorber based on graphene nano-ribbon metamaterial
https://medworm.com/695036223/tunable-multi-band-terahertz-absorber-based-on-graphene-nano-ribbon-metamaterial/
Publication date: Available online 14 May 2019Source: Physics Letters AAuthor(s): Jun WuAbstractThe tunable multi-band selective absorption effect with graphene nano-ribbon metamaterial is investigated. It is achieved by depositing a set of graphene nano-ribbons on a dielectric spacer backed with a metallic mirror. A dual-band and tri-band absorbers are designed to illustrate such multi-band selective absorption behavior. The designed graphene absorbers exhibit near-unity absorption at multiple resonance frequencies, which is attributed to the plasmonic resonance of graphene nano-ribbons with different widths. Moreover, the multiple resonance wavelengths can be tuned in a wide frequency range by changing the Fermi energy and the absorbers possess large angle insensitivity. Last, a Fabry-Pe...Physics Letters AjournalsWed, 15 May 2019 14:36:36 +0100695036223Modeling and simulations of the cascading failure of multiple interdependent R&D networks under risk propagation
https://medworm.com/695036222/modeling-and-simulations-of-the-cascading-failure-of-multiple-interdependent-rd-networks-under-risk/
Publication date: Available online 14 May 2019Source: Physics Letters AAuthor(s): Hui Liu, Naiding Yang, Zhao Yang, Yanlu Zhang, Jianhong LinAbstractIn this paper, we study the robustness of multiple interrelated R&D networks under risk propagation. Firstly, using a bi-partite graph to represent the interrelated R&D networks is emphasized and proposed. Secondly, a risk propagation model is built by defining risk load and risk capacity of each enterprise on a specific R&D network, Thirdly, we use simulations to study risk propagation in interrelated R&D networks. Our results indicate that there exist three critical thresholds to quantify the robustness of R&D networks. Risk propagation in R&D networks is highly affected by the heterogeneity of all enterprises' scales and risk capacities. (S...Physics Letters AjournalsWed, 15 May 2019 14:36:36 +0100695036222Magnetocaloric properties of frustrated tetrahedra-based spin nanoclusters
https://medworm.com/694879117/magnetocaloric-properties-of-frustrated-tetrahedra-based-spin-nanoclusters/
Publication date: Available online 13 May 2019Source: Physics Letters AAuthor(s): M. Mohylna, M. ŽukovičAbstractMagnetization, entropy and magnetocaloric properties of various geometrically frustrated tetrahedra-based Ising antiferromagnetic nanoclusters with corner-, edge-, and face-sharing topologies are studied by exact enumeration. It is found that the studied properties strongly depend on the nanocluster topology and can be very different from those of a single tetrahedron as well as the pyrochlore lattice formed by an infinite number of corner-sharing tetrahedra. From the magnetocaloric point of view an important difference from the latter two systems is the absence of the ground-state zero-magnetization plateau in most of the studied structures, which at low temperatures facilitat...Physics Letters AjournalsWed, 15 May 2019 00:09:29 +0100694879117Graphene based photonic crystal optical filter: Design and exploration of the tunability
https://medworm.com/694879116/graphene-based-photonic-crystal-optical-filter-design-and-exploration-of-the-tunability/
Publication date: Available online 13 May 2019Source: Physics Letters AAuthor(s): Fatemeh Ghasemi, Samad Roshan Entezar, Sepehr RaziAbstractOptical characteristics of two new graphene based photonic crystals are studied in detail. A structure containing alternating layers of graphene and SiO2 slabs is considered as the ideal crystal. The dependency of the photonic band gaps (PBGs) to the dielectric layer thickness and the period number is explored at first step. Potential of the proposed crystal to be used as an optical filter is then investigated. Adding a nonlinear electro-optic polymer as a defect layer, the alterations of the optical features are inspected. Results show that the defect layer insertion causes a resonant mode inside the PBGs. However, the location of the defect layer ins...Physics Letters AjournalsWed, 15 May 2019 00:09:29 +0100694879116Absence of a spontaneous long-range order in a mixed spin-(1/2, 3/2) Ising model on a decorated square lattice due to anomalous spin frustration driven by a magnetoelastic coupling
https://medworm.com/694879115/absence-of-a-spontaneous-long-range-order-in-a-mixed-spin-12-32-ising-model-on-a-decorated-squa/
Publication date: Available online 13 May 2019Source: Physics Letters AAuthor(s): Jozef Strečka, Onofre Rojas, Sergio Martins de SouzaAbstractThe mixed spin-(1/2, 3/2) Ising model on a decorated square lattice, which takes into account lattice vibrations of the spin-3/2 decorating magnetic ions at a quantum-mechanical level under the assumption of a perfect lattice rigidity of the spin-1/2 nodal magnetic ions, is examined via an exact mapping correspondence with the effective spin-1/2 Ising model on a square lattice. Although the considered magnetic structure is in principle unfrustrated due to bipartite nature of a decorated square lattice, the model under investigation may display anomalous spin frustration driven by a magnetoelastic coupling. It turns out that the magnetoelastic coupli...Physics Letters AjournalsWed, 15 May 2019 00:09:29 +0100694879115Effects of the pseudo-gap on the field-induced kinetic energy density of Bi2Sr2CaCu2O8+δ single crystals
https://medworm.com/694879114/effects-of-the-pseudo-gap-on-the-field-induced-kinetic-energy-density-of-bi2sr2cacu2o8-single-cry/
We report on magnetization experiments from which we obtain the field-induced kinetic energy density, Ek, in the superconducting phase of several Bi2Sr2CaCu2O8+δ single crystal samples. The kinetic energy magnitude changes according to the characteristic reduction of the single-electron density of states produced by the pseudogap in the underdoped limit. Moreover, a remarkable peak of Ek occurring at the specific holes density p∼0.18 is related to a van Hove singularity due to the pseudogap closure. We also extracted the superfluid density, ρs. We conclude that Ek and ρs are related to the pseudogap energy scale. This result is understood as an evidence of the coexistence between superconductivity and the pseudogap phenomenon in the Bi2Sr2CaCu2O8+δ cuprate compound. (Source: Physics ...Physics Letters AjournalsWed, 15 May 2019 00:09:29 +0100694879114Editors
https://medworm.com/694879084/editors/
Publication date: 26 June 2019Source: Physics Letters A, Volume 383, Issue 18Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 15 May 2019 00:09:29 +0100694879084Absolute cross sections of ultra-soft x-ray radiation at electron scattering upon atoms and the soft-photons approximation
https://medworm.com/694106440/absolute-cross-sections-of-ultra-soft-x-ray-radiation-at-electron-scattering-upon-atoms-and-the-soft/
Publication date: Available online 10 May 2019Source: Physics Letters AAuthor(s): Aleksei S. Kornev, Boris A. Zon, Miron Ya. AmusiaAbstractWe calculated the cross sections of ultra-soft x-ray bremsstrahlung in electron scattering upon Ar, Kr and Xe. The results are consistent with the absolute values of the differential cross sections measured by Gnatchenko et al. (2009) [17] for scattering electrons with an energy of 600 eV on these atoms. (Source: Physics Letters A)Physics Letters AjournalsSat, 11 May 2019 23:12:52 +0100694106440Fractional spin-vortex states in F = 2 spinor Bose-Einstein condensates
https://medworm.com/694106439/fractional-spin-vortex-states-in-f2-spinor-bose-einstein-condensates/
Publication date: Available online 10 May 2019Source: Physics Letters AAuthor(s): Liang-Liang Xu, Yong-Kai Liu, Shiping Feng, Shi-Jie YangAbstractStable fractional vortices are numerically generated in the two-dimensional rotating F=2 spinor Bose-Einstein condensates. We demonstrate the existence of 14-vortex state or 12-vortex state in the biaxial nematic phase, and 13-vortex state in the cyclic phase. At fast rotation a lattice of fractional vortex in the spin space emerges. Intriguingly, the integral spin-winding of the whole system does not increase with the rotation speed but equals to a simple fraction. (Source: Physics Letters A)Physics Letters AjournalsSat, 11 May 2019 23:12:52 +0100694106439Tuning the optical properties of Fe-Au core-shell nanoparticles with spherical and spheroidal nanostructures
https://medworm.com/694106438/tuning-the-optical-properties-of-fe-au-core-shell-nanoparticles-with-spherical-and-spheroidal-nanost/
Publication date: Available online 10 May 2019Source: Physics Letters AAuthor(s): Pradeep Bhatia, S.S. Verma, M.M. SinhaAbstractPresent research interest is to highlight on the manufacturing of core-shell nanoparticles because of core activity with unique properties and surface modification by a shell in the diverse fields (e.g. optoelectronic, catalysis and magneto-optics). In addition, the combined optical properties of magnetic-plasmonic core-shell NPs make them ideal candidates for many applications in biomedical fields. The influence of Fe-core and Au-shell for the formation of the core-shell viz. spherical and spheroidal nanostructures is studied using the discrete dipole approximation method. DDA is an approximation method and its accuracy is compared to Mie theory results for spher...Physics Letters AjournalsSat, 11 May 2019 23:12:52 +0100694106438Editors
https://medworm.com/694106411/editors/
Publication date: 16 June 2019Source: Physics Letters A, Volume 383, Issue 17Author(s): (Source: Physics Letters A)Physics Letters AjournalsSat, 11 May 2019 23:12:52 +0100694106411Dual solutions and stability analysis of flow and heat transfer of Casson fluid over a stretching sheet
https://medworm.com/693793386/dual-solutions-and-stability-analysis-of-flow-and-heat-transfer-of-casson-fluid-over-a-stretching-sh/
Publication date: Available online 30 April 2019Source: Physics Letters AAuthor(s): M. Hamid, M. Usman, Z.H. Khan, R. Ahmad, W. WangAbstractThe aim of the current study is to find out the dual solutions of the two-dimensional magnetohydrodynamic (MHD) flow of Casson fluid and heat transfer over the stretching sheet. The focus of the study is to examine the linear thermal radiation effects on dual solutions for both the steady and unsteady flow of Casson fluid over the stretching sheet under the influence of uniform magnetic field. The governing equations are formed as system of partial differential equations (PDEs). Using suitable transformations, the system of PDEs are converted into favorable nonlinear system of ordinary differential equations (ODEs). Simulations are performed in Maple 2...Physics Letters AjournalsFri, 10 May 2019 19:03:26 +0100693793386Spin thermoelectricity in dualhydrogenated zigzag silicene nanoribbons with surface adsorptions
https://medworm.com/693793364/spin-thermoelectricity-in-dualhydrogenated-zigzag-silicene-nanoribbons-with-surface-adsorptions/
Publication date: Available online 9 May 2019Source: Physics Letters AAuthor(s): Yushen Liu, Xiaoshuang Chen, Xifeng YangAbstractThe buckled structure of silicene provides a feasible pathway to influence its electric and magnetic properties via surface adsorptions. Here, we investigate the magnetic and spin thermoelectric transport properties of dual-hydrogenated zigzag silicene nanoribbons (ZSiNRs) without/with the hydrogen adsorption. The band gaps for two spin channels in ZSiNRs under the hydrogen adsorption are shifted near the Fermi level, leading to the appearance of spin Seebeck effect. Using a temperature difference, one can derive the carriers with the different spin index to flow in the opposite direction. Moreover, a large rectification ratio close to 105 at room temperature is ...Physics Letters AjournalsFri, 10 May 2019 19:03:26 +0100693793364Growth curve based label propagation algorithm for community detection
https://medworm.com/693639441/growth-curve-based-label-propagation-algorithm-for-community-detection/
Publication date: Available online 8 May 2019Source: Physics Letters AAuthor(s): Xue LiAbstractHow to better and faster identify the community structure is a hot issue in complex networks. During the past decades, various attempts have been made to solve this issue. Amongst them, without doubt, label propagation algorithm (LPA) is one of the most satisfying answers, especially for large-scale networks. However, it has one major flaw that when the community structure is not clear enough, a monster community tends to form. To address this issue, we set a growth curve for communities, gradually increasing from a low capacity to a higher capacity over time. Further, we improve the mechanism of label choosing for small communities to escape from local maximum. The experimental results on both s...Physics Letters AjournalsFri, 10 May 2019 04:15:55 +0100693639441Spatiotemporal dynamics of the polarisation state of laser radiation performed by lens-axicon combinations
https://medworm.com/693639440/spatiotemporal-dynamics-of-the-polarisation-state-of-laser-radiation-performed-by-lens-axicon-combin/
Publication date: Available online 8 May 2019Source: Physics Letters AAuthor(s): S.N. Khonina, S.G. Volotovsky, A.V. Ustinov, A.P. PorfirevAbstractSpatiotemporal dynamics of the polarisation state of laser radiation performed by lens-axicon combinations were investigated theoretically and numerically in the paraxial regime. We demonstrate that in this case, while the static polarisation state does not change, various features are observed in the temporal dynamics, including spiral trajectories of the field components, transformation of the polarisation state and the “disappearance” of the light field at some time moments of the harmonic period. The results obtained can be useful for understanding the effects of spatiotemporal polarisation transformations of laser radiation, which is cr...Physics Letters AjournalsFri, 10 May 2019 04:15:55 +0100693639440Dynamical precession of spin in the two-dimensional spin-orbit coupled systems
https://medworm.com/693639439/dynamical-precession-of-spin-in-the-two-dimensional-spin-orbit-coupled-systems/
Publication date: Available online 8 May 2019Source: Physics Letters AAuthor(s): Tsung-Wei Chen, Zhi-Yang Huang, Dah-Wei ChiouAbstractWe investigate the spin dynamics in the two-dimensional spin-orbit coupled system subject to an in-plane (x-y plane) constant electric field, which is assumed to be turned on at the moment t=0. The equation of spin precession in linear response to the switch-on of the electric field is derived in terms of Heisenberg's equation by the perturbation method up to the first order of the electric field. The dissipative effect, which is responsible for bringing the dynamical response to an asymptotic result, is phenomenologically implemented à la the Landau-Lifshitz-Gilbert equation by introducing damping terms upon the equation of spin dynamics. Mediated by the d...Physics Letters AjournalsFri, 10 May 2019 04:15:55 +0100693639439Direct calculation of time varying Aharonov-Bohm effect
https://medworm.com/693639438/direct-calculation-of-time-varying-aharonov-bohm-effect/
Publication date: Available online 8 May 2019Source: Physics Letters AAuthor(s): S. Rai Choudhury, Shobhit MahajanAbstractThe Aharonov-Bohm effect (ABE) for steady magnetic fields is a well known phenomenon. However, if the current in the infinite solenoid that creates the magnetic field is time-dependent, that is in the presence of both magnetic and electric fields, there is no agreement whether the effect would be present. In this note, we try to investigate time varying ABE by a direct calculation in a set-up with a weak time dependent magnetic field. We find that the electric field arising out of the time-varying magnetic field in the path of the electrons does not enter the action integral but only changes the path of the electron from the source to the slits and then on to the detect...Physics Letters AjournalsFri, 10 May 2019 04:15:55 +0100693639438Kalman filter-based phase estimation of continuous-variable quantum key distribution without sending local oscillator
https://medworm.com/693338084/kalman-filter-based-phase-estimation-of-continuous-variable-quantum-key-distribution-without-sending/
Publication date: Available online 7 May 2019Source: Physics Letters AAuthor(s): Yu Su, Ying Guo, Duan HuangAbstractPhase estimation is one of the crucial procedures in continuous-variable quantum key distribution without sending local oscillator (LLO-CVQKD), aiming at compensating the phase drift in post-processing. To decrease the phase noise caused by the phase drift and measurement error, we propose Kalman filter-based phase noise estimation of LLO-CVQKD, which involves the measurements and filtering through exploiting the small amplitude reference pulses, achieving the accurate phase noise estimation. Simulation results indicate that Kalman filter-based phase noise estimation is capable of reducing measurement error and phase noise, while increasing the secret key rate by 7 times. (So...Physics Letters AjournalsWed, 08 May 2019 23:39:29 +0100693338084Non-Markovianity in the presence of multiple thermal environments via collision model
https://medworm.com/693338083/non-markovianity-in-the-presence-of-multiple-thermal-environments-via-collision-model/
Publication date: Available online 7 May 2019Source: Physics Letters AAuthor(s): Qi Zhang, Zhong-Xiao Man, Yun-Jie XiaAbstractBy means of the collision model, we study the non-Markovianity of an open quantum system S being coupled to M thermal reservoirs. In our model, each reservoir is modeled as a chain of ancillas whose intracollisions account for the occurrence of non-Markovian dynamics. We show that by incorporating M reservoir ancillas into the system, the non-Markovian dynamics of S can be embedded in the extended system that experiences a completely Markovian dynamics. The number M of involved reservoirs can thus be identified as the memory depth and determines the degree of the non-Markovianity. In the equilibrium case with identical temperatures for all the reservoirs, we show th...Physics Letters AjournalsWed, 08 May 2019 23:39:29 +0100693338083Simulating the Klein tunneling of pseudospin-one Maxwell particles with trapped ions
https://medworm.com/693338082/simulating-the-klein-tunneling-of-pseudospin-one-maxwell-particles-with-trapped-ions/
Publication date: Available online 7 May 2019Source: Physics Letters AAuthor(s): Peng He, Xin Shen, Dan-Wei Zhang, Shi-Liang ZhuAbstractWe propose an experimental scheme to simulate and observe the Klein tunneling of relativistic Maxwell particles with trapped ions. We explore the scattering dynamics of the pseudospin-one Maxwell particles and demonstrate that the scattered state should be a superposition of a reflection state, a localization state, and a transmission state. The probabilities of these states can be analytically obtained by the approach of Landau-Zener transition. We further show that the Maxwell Hamiltonian and the associated scattering dynamics can be mimicked with two trapped ions. The Maxwell spinors are encoded by three internal states of the first ion, the position an...Physics Letters AjournalsWed, 08 May 2019 23:39:29 +0100693338082Activation mechanisms of silver toward CO oxidation by tungsten carbide substrate: A density functional theory study
https://medworm.com/693338081/activation-mechanisms-of-silver-toward-co-oxidation-by-tungsten-carbide-substrate-a-density-functio/
Publication date: Available online 7 May 2019Source: Physics Letters AAuthor(s): Yuling Zhao, Xilin Zhang, Zongxian YangAbstractThe development of efficient catalysts for low temperature CO oxidation is important to the application of fuel cells. In this work, we report that the Ag monolayer on WC (0001) surface (AgML/WC) could effectively catalyze CO oxidation through the L-H mechanism (CO + O2 → OOCO → CO2 + O). The most sluggish reaction step is suggested to be CO + O → CO2 with a barrier of 0.48 eV, which is 1.21 eV lower than the barrier of O2 dissociation. The electronic structure and d-band center analyses demonstrate that the promoted activity may originate from the synergistic effect between Ag monolayer and WC. The present study is conducive to design new efficient and cost...Physics Letters AjournalsWed, 08 May 2019 23:39:29 +0100693338081Thermal transport properties in monolayer GeS
https://medworm.com/693034431/thermal-transport-properties-in-monolayer-ges/
Publication date: Available online 6 May 2019Source: Physics Letters AAuthor(s): Yongqing Wang, Xiuxian Yang, Yuanfang ShangAbstractUtilizing the first-principle techniques combined with the Boltzmann transport equation, we investigate the thermal transport properties of monolayer GeS. The calculated lattice thermal conductivity κL is fairly low, e.g., 11.76 (12.53) Wm−1K−1 at 300 K, along the x (y) axis, which is much lower than the values for phosphorene, monolayer MoS2, graphene, etc. Our analysis reveals that the low lattice thermal conductivity is resulted from the strong three-phonon scattering process and the low phonon group velocity. Due to the weak anisotropy of GeS, we study the contribution of each phonon branch to the heat transport along x and y axis, and find that the l...Physics Letters AjournalsTue, 07 May 2019 19:03:26 +0100693034431High-pressure phases and pressure-induced phase transition of MoN6 and ReN6
https://medworm.com/693034430/high-pressure-phases-and-pressure-induced-phase-transition-of-mon6-and-ren6/
We report two new nitrogen-rich Transition metal nitrides, MoN6 and ReN6, by crystal structure searching technique. Under high pressure, MoN6 will undergo phase transition (from R-3m to Pm-3 phase) at 54 GPa, and ReN6 always keep the R-3m phase in the pressure range from 50 to 100 GPa. There are benzene-like six-membered “N6” rings with nitrogen single bonds in the R-3m phase structures, indicating that MoN6 and ReN6 are expected to be the high-energy-density materials. (Source: Physics Letters A)Physics Letters AjournalsTue, 07 May 2019 19:03:26 +0100693034430Transparent quantum graphs
https://medworm.com/692257623/transparent-quantum-graphs/
Publication date: Available online 3 May 2019Source: Physics Letters AAuthor(s): J.R. Yusupov, K.K. Sabirov, M. Ehrhardt, D.U. MatrasulovAbstractWe consider quantum graphs with transparent branching points. To design such networks, the concept of transparent boundary conditions is applied to the derivation of the vertex boundary conditions for the linear Schrödinger equation on metric graphs. This allows to derive simple constraints, which make usual Kirchhoff-type boundary conditions at the vertex equivalent to the transparent ones. The approach is applied to quantum star and tree graphs. However, extension to more complicated graph topologies is rather straightforward. (Source: Physics Letters A)Physics Letters AjournalsSat, 04 May 2019 17:06:30 +0100692257623Acoustic absorbers at low frequency based on split-tube metamaterials
https://medworm.com/692257622/acoustic-absorbers-at-low-frequency-based-on-split-tube-metamaterials/
Publication date: Available online 3 May 2019Source: Physics Letters AAuthor(s): Peng Wu, Qianjin Mu, Xiaoxiao Wu, Li Wang, Xin Li, Yuqing Zhou, Shuxia Wang, Yingzhou Huang, Weijia WenAbstractThe remarkable properties of acoustic metamaterials have attracted massive researches and applications, especially on low-frequency sound absorptions. Currently, most of the acoustic metamaterial absorbers employ resonances in plastic cavities, and their structural strengths are important in many circumstances, especially in harsh environment. However, studies of metamaterials including this point are very scarce. Here, we propose an acoustic metamaterial for low-frequency (<500 Hz) absorptions, composed of three nested square split tubes with inverted opening directions. The efficiency of the abs...Physics Letters AjournalsSat, 04 May 2019 17:06:30 +0100692257622Thickness-dependent magnetic order and phase-transition dynamics in epitaxial Fe-rich FeRh thin films
https://medworm.com/692257621/thickness-dependent-magnetic-order-and-phase-transition-dynamics-in-epitaxial-fe-rich-ferh-thin-film/
Publication date: Available online 3 May 2019Source: Physics Letters AAuthor(s): C.Q. Yu, H. Li, Y.M. Luo, L.Y. Zhu, Z.H. Qian, T.J. ZhouAbstractThe control of magnetic order and phase-transition dynamics by various means is a key towards low-power spintronics. Here, we report a control on magnetic order and phase-transition dynamics by tuning film thickness in epitaxial FeRh films. Reduction of film thicknesses from 200 nm to 5 nm results in an anti-ferromagnetic to ferromagnetic phase change, accompanied by a 0.55% lattice expansion for c-axis. The phase-transition dynamics is highly dependent on the film thickness, and involves the release and recovery of lattice strain that results in a lower transition temperature and larger thermal hysteresis in thinner films. The findings help to un...Physics Letters AjournalsSat, 04 May 2019 17:06:30 +0100692257621Classical random walk with memory versus quantum walk on a one-dimensional infinite chain
https://medworm.com/692257620/classical-random-walk-with-memory-versus-quantum-walk-on-a-one-dimensional-infinite-chain/
Publication date: Available online 3 May 2019Source: Physics Letters AAuthor(s): Jingfeng Wu, Peng Xu, Xuanmin ZhuAbstractQuantum walk is a very useful tool for building quantum algorithms due to the faster spreading of probability distributions as compared to a classical random walk. Comparing the spreading of the probability distributions of a quantum walk with that of a mnemonic classical random walk on a one-dimensional infinite chain, we find that the classical random walk could have a faster spreading than that of the quantum walk conditioned on a finite number of walking steps. Quantum walk surpasses classical random walk with memory in spreading speed when the number of steps is large enough. However, in such a situation, quantum walk would seriously suffer from decoherence. Theref...Physics Letters AjournalsSat, 04 May 2019 17:06:30 +0100692257620Pauli semigroups and unistochastic quantum channels
https://medworm.com/692257619/pauli-semigroups-and-unistochastic-quantum-channels/
Publication date: Available online 3 May 2019Source: Physics Letters AAuthor(s): Zbigniew Puchała, Łukasz Rudnicki, Karol ŻyczkowskiAbstractWe adopt the perspective of similarity equivalence, in gate set tomography called the gauge, to analyze various properties of quantum operations belonging to a semigroup, Φ=eLt, and therefore given through the Lindblad operator. We first observe that the non unital part of the channel decouples from the time evolution. Focusing on unital operations we restrict our attention to the single-qubit case, showing that the semigroup embedded inside the tetrahedron of Pauli channels is bounded by the surface composed of product probability vectors and includes the identity map together with the maximally depolarizing channel. Consequently, every member of ...Physics Letters AjournalsSat, 04 May 2019 17:06:30 +0100692257619Relaxation dynamics in a stochastic bosonic Josephson junction
https://medworm.com/692101309/relaxation-dynamics-in-a-stochastic-bosonic-josephson-junction/
Publication date: Available online 2 May 2019Source: Physics Letters AAuthor(s): Dionisis Stefanatos, Emmanuel PaspalakisAbstractWe consider a bosonic Josephson junction in the Bose-Hubbard two-mode approximation where some of the parameters are corrupted by physically meaningful noise processes and study the corresponding relaxation dynamics towards its equilibrium state. We show with numerical simulations that this model can essentially capture all the important features observed in a recent experiment regarding the relaxation dynamics in one-dimensional bosonic Josephson junctions, namely the damped oscillations of the population imbalance and the relative phase, as well as the large final coherence factor. We expect that this work will further motivate research about the origin of rela...Physics Letters AjournalsSat, 04 May 2019 02:09:25 +0100692101309Size effect on electric-double-layer capacitances of conducting structures
https://medworm.com/692101308/size-effect-on-electric-double-layer-capacitances-of-conducting-structures/
Publication date: Available online 2 May 2019Source: Physics Letters AAuthor(s): Fuqian YangAbstractThe charge storage in an electrical double-layer capacitor is dependent on the accumulation of ions on the interface between electrolyte and conducting material and the spatial distribution of ions in electrolyte. In this work, we study the effect of local curvature on the concentration of ions on the interface between electrolyte and electrode from the framework of thermodynamics and incorporate the concentration of ions on the interface in the analysis of the spatial distribution of ions for symmetric binary electrolytes. Semi-analytical results of the integral electrical-double-layer capacitances per unit area under the condition of large Debye-Hückel constant are obtained for spherical ...Physics Letters AjournalsSat, 04 May 2019 02:09:25 +0100692101308The influence of coupling between chains on the conductivity of atomic carbon chains
https://medworm.com/692101307/the-influence-of-coupling-between-chains-on-the-conductivity-of-atomic-carbon-chains/
Publication date: Available online 2 May 2019Source: Physics Letters AAuthor(s): Zhewen Liang, Xiaodong Xu, Yingjie Jiang, Weiqi Li, Qiang Wang, Guiling Zhang, Wei Quan Tian, Yongyuan JiangAbstractThis work presents a theoretical investigation on the electronic properties of double atomic carbon chains bridging graphene electrodes with density functional theory in combination with non-equilibrium Green's function. The influence of strain on the conductance of atomic carbon chains is significant. However, the coupling effect between adjacent chains dominates the intrinsic transport of double atomic carbon chains. For the coupled double atomic chains, the electron conductance of even-numbered atomic chains is significantly enhanced, while the electron conductance of odd-numbered atomic chain...Physics Letters AjournalsSat, 04 May 2019 02:09:25 +0100692101307Thomson 4/3 problem leads to nonlocal continuous charges with Poincaré radial stresses and zero electromagnetic inertia
https://medworm.com/692101306/thomson-43-problem-leads-to-nonlocal-continuous-charges-with-poincar-radial-stresses-and-zero-ele/
Publication date: Available online 2 May 2019Source: Physics Letters AAuthor(s): I.E. BulyzhenkovAbstractInertia-free electricity in Maxwell’s equations is consistent with the elementary radial charge. The internal Poincaré stresses stabilize an extended electric charge and participate in zeroing its integral four-momentum. The global overlap of extended particles reinterprets classical physics in nondual terms of elementary material fields without areas of empty space. Measurements in macroscopic experiments can be explained by purely field carriers of electric energy. New probes beyond quantum nonlocality could falsify the point charge approximation and the empty space paradigm of dual electrodynamics. (Source: Physics Letters A)Physics Letters AjournalsSat, 04 May 2019 02:09:25 +0100692101306Electronic transport on graphene armchair-edge nanoribbons with Fermi velocity and potential barriers
https://medworm.com/691478890/electronic-transport-on-graphene-armchair-edge-nanoribbons-with-fermi-velocity-and-potential-barrier/
Publication date: Available online 30 April 2019Source: Physics Letters AAuthor(s): A.C.S. Nascimento, R.P.A. Lima, M.L. Lyra, J.R.F. LimaAbstractThe transport properties of Dirac fermions through armchair-edge graphene nanoribbons (AGNRs) with a single and double rectangular Fermi velocity vF and electrostatic potential U barriers is investigated. We employ a transfer matrix method (TMM) to compute the transmission coefficient of the full set of propagating mode which is used to obtain the conductance and Fano factor spectra for both metallic and semiconducting nanoribbons. We show that a reduced Fermi velocity within the barrier region can partially suppress the backscattering resulting from the electrostatic potential. In a double barrier structure, the emergence of high-order transmitt...Physics Letters AjournalsWed, 01 May 2019 16:15:22 +0100691478890Dual solutions and stability analysis of flow and heat transfer of Casson fluid over the stretching sheet
https://medworm.com/691478889/dual-solutions-and-stability-analysis-of-flow-and-heat-transfer-of-casson-fluid-over-the-stretching-/
Publication date: Available online 30 April 2019Source: Physics Letters AAuthor(s): M. Hamid, M. Usman, Z.H. Khan, R. Ahmad, W. WangAbstractThe aim of the current study is to find out the dual solutions of the two-dimensional magnetohydrodynamic (MHD) flow of Casson fluid and heat transfer over the stretching sheet. The focus of the study is to examine the linear thermal radiation effects on dual solutions for both the steady and unsteady flow of Casson fluid over the stretching sheet under the influence of uniform magnetic field. The governing equations are formed as system of partial differential equations (PDEs). Using suitable transformations, the system of PDEs are converted into favorable nonlinear system of ordinary differential equations (ODEs). Simulations are performed in Maple 2...Physics Letters AjournalsWed, 01 May 2019 16:15:22 +0100691478889Editors
https://medworm.com/691478861/editors/
Publication date: 6 June 2019Source: Physics Letters A, Volume 383, Issue 16Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 01 May 2019 16:15:22 +0100691478861Dynamical switching and memory via incoherent pump assisted optical bistability
https://medworm.com/691323698/dynamical-switching-and-memory-via-incoherent-pump-assisted-optical-bistability/
Publication date: Available online 29 April 2019Source: Physics Letters AAuthor(s): Ya-Nan Li, Yu-Yuan Chen, Ren-Gang Wan, Hong-Wei YanAbstractWe analyze the dynamical behavior of all-optical switching and memory based on tunable optical bistability in a three-level Λ-type atomic system driven by a probe field circulating in an optical ring cavity, a coherent coupling field and an incoherent pump field outside cavity. Owing to the incoherent pump process, the absorption and Kerr nonlinearity near the atomic resonance change dramatically as a result of varied population distribution and atomic coherence, and then the switch-up and switch-down thresholds, as well as the width (or area) of bistable curve, can be manipulated effectively. By varying the intensity of either coherent coupling fi...Physics Letters AjournalsWed, 01 May 2019 01:42:30 +0100691323698Electronic structures and magnetic properties of CrSiTe3 single-layer nanoribbons
https://medworm.com/691323697/electronic-structures-and-magnetic-properties-of-crsite3-single-layer-nanoribbons/
In this study, we systematically investigate the stability, electronic structures and magnetic properties of CrSiTe3 single-layer nanoribbons with different edge configurations and ribbon widths using first-principles calculations. The results show that the edge energies (less than 0.4 eV/Å) for all studied CrSiTe3 nanoribbons are much lower than that of graphene and many transition-metal dichalcogenide nanoribbons, indicating their stability and easy formation. Compared to the CrSiTe3 monolayer with ferromagnetic semiconductor characterictics, some of CrSiTe3 nanoribbons (N-SiCr-ZNRs, N-Te-ZNRs, N-TeCr-ANRs and N-Te-ANRs) become half-metal due to the hybridization between the d orbitals of edge Cr atoms and the p orbitals of edge Te atoms. While N-SiTe-ANRs are bipolar magnetic semicondu...Physics Letters AjournalsWed, 01 May 2019 01:42:30 +0100691323697Coupling analysis of screwing motion of double-walled carbon nanotubes
https://medworm.com/691323696/coupling-analysis-of-screwing-motion-of-double-walled-carbon-nanotubes/
Publication date: Available online 30 April 2019Source: Physics Letters AAuthor(s): Liang Chen, Wu-Gui Jiang, Hang Zou, Xi-Qiao Feng, Qing-Hua Qin, Xin LiAbstractAs the inner tube is excited from a rotation frequency at a separation distance, the inner tube will generate a reciprocating screwing motion. In this work, this coupling effect is investigated theoretically. The van der Waals force between two carbon nanotubes is expressed in a simple form of Fourier series so that the coupled nonlinear differential equations can be quickly solved. The proposed approach is thousands of times faster than the traditional method, which makes it possible to fit the coupling coefficients. As a result, expressions for the coefficients of the coupled equations are given. It is observed that a larger ini...Physics Letters AjournalsWed, 01 May 2019 01:42:30 +0100691323696Nuclear probes of an out-of-equilibrium plasma at the highest compression
https://medworm.com/691323695/nuclear-probes-of-an-out-of-equilibrium-plasma-at-the-highest-compression/
We report the highest compression reached in laboratory plasmas using eight laser beams, E≈laser12 kJ, τlaser=2 ns in third harmonic on a CD2 target at the ShenGuang-II Upgrade (SGII-Up) facility in Shanghai, China. We estimate the deuterium density ρD=2.0±0.9 kg/cm3, and the average kinetic energy of the plasma ions less than 1 keV. The highest reached areal density ΛρD=4.8±1.5 g/cm2 was obtained from the measured ratio of the sequential ternary fusion reactions (dd→t+p and t+d→α+n) and the two body reaction fusions (dd→3He+n). At such high densities, sequential ternary and also quaternary nuclear reactions become important as well (i.e. n(14.1 MeV) + 12C → n'+12C* etc.) resulting in a shift of the neutron (and proton) kinetic energies from their birth values. The Down Sc...Physics Letters AjournalsWed, 01 May 2019 01:42:30 +0100691323695Novel electric field effects on Landau levels in multi-Weyl semimetals
https://medworm.com/691323694/novel-electric-field-effects-on-landau-levels-in-multi-weyl-semimetals/
Publication date: Available online 30 April 2019Source: Physics Letters AAuthor(s): Amit GuptaAbstractMulti-Weyl semimetals (WSMs) have an anisotropic non-linear dispersion along a 2-D plane and a linear dispersion in an orthogonal direction. They have topological charge ‘n' and are created when two or multiple Weyl points or nodes with nonzero net monopole charge are brought together onto a high-symmetry point. We study the perturbation corrections up to second order of such multi-WSMs in crossed electric (E) and magnetic (B) fields in the low electric field approximation. As a result, the first order correction lifts only n-fold degeneracy of the lowest Landau levels (LLs) while the higher Landau levels are modified due to the second order perturbation. We study the signatures of these...Physics Letters AjournalsWed, 01 May 2019 01:42:30 +0100691323694Linear and nonlinear excitations in warm dense matter
https://medworm.com/691323693/linear-and-nonlinear-excitations-in-warm-dense-matter/
Publication date: Available online 30 April 2019Source: Physics Letters AAuthor(s): M. Akbari-Moghanjoughi, M. MohammadnejadAbstractSmall and large amplitude linear and nonlinear ion acoustic and Langmuir waves are investigated for plasma with the generalized equation of state (EoS). This EoS covers a wide range of energy-density conditions from dilute classical regime up to the relativistically degenerate matter. Investigation shows that the linear dispersion and localized excitations of ion acoustic waves are significantly affected by the plasma parameters. It is also found that the criterion for ordinary soliton existence is significantly different for fully degenerate and nondegenerate plasma regimes with given electron temperature. In the nondegenerate regime, bright solitons form onl...Physics Letters AjournalsWed, 01 May 2019 01:42:30 +0100691323693Effect of permanent magnet configuration on discharge characteristics in cylindrical Hall thrusters
https://medworm.com/690544669/effect-of-permanent-magnet-configuration-on-discharge-characteristics-in-cylindrical-hall-thrusters/
Publication date: Available online 26 April 2019Source: Physics Letters AAuthor(s): Shengtao Liang, Hui Liu, Daren YuAbstractMagnetic field design is important in cylindrical Hall thrusters and using permanent magnets to generate magnetic field is very promising in the future. In two typical permanent magnet configurations (i.e., ring and cylindrical configurations) of cylindrical Hall thrusters, discharge characteristics are compared in this paper through the experiments and simulations. The study shows that the cylindrical configuration can bring about higher thruster performance in the same working condition. The reason is that the potential drop of the cylindrical configuration is mainly concentrated in the channel, which is beneficial for the electrons to obtain energy to promote the ...Physics Letters AjournalsSun, 28 Apr 2019 02:15:56 +0100690544669Origin of the hardness in the monolayer nanographene
https://medworm.com/690544668/origin-of-the-hardness-in-the-monolayer-nanographene/
Publication date: Available online 26 April 2019Source: Physics Letters AAuthor(s): Yasin Göktürk YıldızAbstractIn this paper, we investigated the lattice distorsion displacement effects (LDDE) on magnetizations versus temperature in a monolayer nanographene (MLNG) by using effective field theory developed by Kaneyoshi. To obtain the LDDE, we used the twinning angle (Θ) of the zigzag edge of the MLNG and obtain the M-T curves for Θ=100-1800 with 10 steps. We find that MLNG has a minimum Curie temperature (TCmin=2.738) for a certain critical twinning angle (ΘCTA=1300) of the zigzag edge of the MLNG. The TC increases (TC>TCmin) as the Θ increases or decreases from the ΘCTA=1300 (both Θ<ΘCTA and at Θ>ΘCTA cases). Since the hardness is directly proportional with the Tc, the ha...Physics Letters AjournalsSun, 28 Apr 2019 02:15:56 +0100690544668A comparative study of local quantum Fisher information and local quantum uncertainty in Heisenberg XY model
https://medworm.com/690544667/a-comparative-study-of-local-quantum-fisher-information-and-local-quantum-uncertainty-in-heisenberg-/
Publication date: Available online 26 April 2019Source: Physics Letters AAuthor(s): A. Slaoui, L. Bakmou, M. Daoud, R. Ahl LaamaraAbstractRecently, it has been shown that the quantum Fisher information via local observables and via local measurements (i.e., local quantum Fisher information (LQFI)) is a central concept in quantum estimation and quantum metrology and captures the quantumness of correlations in multi-component quantum system (Kim et al. (2018) [28]). This new discord-like measure is very similar to the quantum correlations measure called local quantum uncertainty (LQU). In the present study, we have revealed that LQU is bounded by LQFI in the phase estimation protocol. Also, a comparative study between these two quantum correlations quantifiers is addressed for the quantum He...Physics Letters AjournalsSun, 28 Apr 2019 02:15:56 +0100690544667Electronic structures of twist-stacked 1T-TaS2 bilayers
https://medworm.com/690544666/electronic-structures-of-twist-stacked-1t-tas2-bilayers/
Publication date: Available online 26 April 2019Source: Physics Letters AAuthor(s): Yunting Li, Huaping Xiao, Pan Zhou, Juexian CaoAbstractBy using first-principles calculations, we investigate the effect of the twisted angle (θ) on the electronic structures of two types of 1T-TaS2 bilayers. Our calculation show that with the increase of twisted angles, the formation energy increases for the two types of structures and the band gap for Type II increases while the Type I structures experience a metal-semiconductor transition. The changes are mainly resulted from the interlayer interaction and the redistribution of charge density induced by in-plane distortion. It is found that the structure with θ=32.2° for the Type I is a possible metastable charge-density-wave (CDW) phase. The findings...Physics Letters AjournalsSun, 28 Apr 2019 02:15:56 +0100690544666Nanoscale thermal cloaking by in-situ annealing silicon membrane
https://medworm.com/690231808/nanoscale-thermal-cloaking-by-in-situ-annealing-silicon-membrane/
Publication date: Available online 25 April 2019Source: Physics Letters AAuthor(s): Yida Liu, Yanhua Cheng, Run Hu, Xiaobing LuoAbstractWith the advent of thermal metamaterials, many new thermal functionalities have been proposed, like thermal cloaking, concentrating, etc. However, these thermal functionalities are based on the transformation thermotics or scattering cancellation technique, which, derived from Fourier's law, cannot apply to the micro-/nanoscale counterparts. In this paper, we design a nanoscale thermal cloak based on a crystalline silicon (Si) membrane and investigate the in-plane phonon transport via non-equilibrium molecular dynamics (NEMD) simulation by in-situ tuning the thermal conductivity of the thermal cloak from crystalline Si to amorphous Si. The two-dimensional ...Physics Letters AjournalsFri, 26 Apr 2019 22:03:43 +0100690231808Detecting chaos in fractional-order nonlinear systems using the smaller alignment index
https://medworm.com/690231807/detecting-chaos-in-fractional-order-nonlinear-systems-using-the-smaller-alignment-index/
Publication date: Available online 25 April 2019Source: Physics Letters AAuthor(s): Shaobo He, Kehui Sun, Yuexi PengAbstractThe identification between chaos and ordered states in fractional-order chaotic systems is a challenge as well as a hot topic due to the complex of fractional calculus. In this paper, the smaller alignment index (SALI) is developed to detect chaos in the fractional-order chaotic systems by introducing the fractional-order tangent systems. Numerical simulation is carried out based on the fractional-order simplified Lorenz system and the fractional-order Hénon map, which are continuous chaotic system and discrete chaotic system, respectively. It shows that the proposed method is effective for distinguishing chaos and order in different kinds of fractional-order chaotic...Physics Letters AjournalsFri, 26 Apr 2019 22:03:43 +0100690231807Magnetic behavior, Griffiths phase and magneto-transport study in 3d based nano-crystalline double perovskite Pr2CoMnO6
https://medworm.com/690075741/magnetic-behavior-griffiths-phase-and-magneto-transport-study-in-3d-based-nano-crystalline-double-p/
Publication date: Available online 24 April 2019Source: Physics Letters AAuthor(s): Ilyas Noor Bhatti, Imtiaz Noor Bhatti, Rabindra Nath Mahato, M.A.H. AhsanAbstractDouble perovskite (DP) oxide material receive extensive research interest due to exciting physical properties with potential technological application. 3d based DP oxides are promising for exciting physics like magnetodielectric, ferroelectric, Griffiths phase, etc., specially Co/Mn DPs are gaining much research interest. In this paper we present the study of magnetic phase and transport properties in nano-crystalline Pr2CoMnO6 a 3d based double perovskite compound. This material shows a paramagnetic (PM) to ferromagnetic (FM) phase transition below 173 K marked by a rapid increase in magnetic moment due to spin ordering. We fo...Physics Letters AjournalsFri, 26 Apr 2019 07:39:29 +0100690075741Exchange bias behavior and magnetocaloric effect in Ni2In-type Mn7Sn4 alloy
https://medworm.com/690075740/exchange-bias-behavior-and-magnetocaloric-effect-in-ni2in-type-mn7sn4-alloy/
Publication date: Available online 24 April 2019Source: Physics Letters AAuthor(s): Zhishuo Zhang, Xiaohua Luo, Ying Song, Kai Liu, Shengcan Ma, Changcai Chen, Yuxi Zhang, Hai Zeng, Xuanwei Zhao, Qingzheng Jiang, Sajjad Ur Rehman, Zhenchen ZhongAbstractIn this work, the exchange bias behavior and magnetocaloric effect have been studied in Mn7Sn4 alloy. The X-ray powder diffraction pattern recorded at room temperature indicates that the sample crystallizes in a single phase with Ni2In-type hexagonal structure (space group P63/mmc). The maximum magnetic entropy change value across paramagnetic/ferrimagnetic transition is about 3.3 J kg−1 K−1 under the magnetic field change of μ0ΔH=0-5T. With further cooling, the reentrant spin-glass-like state is obtained below 150 K, for whi...Physics Letters AjournalsFri, 26 Apr 2019 07:39:29 +0100690075740Quantum algorithm for total least squares data fitting
https://medworm.com/690075738/quantum-algorithm-for-total-least-squares-data-fitting/
Publication date: Available online 24 April 2019Source: Physics Letters AAuthor(s): Hefeng Wang, Hua XiangAbstractThe total least squares (TLS) method is widely used in data-fitting. Compared with the least squares fitting method, the TLS fitting takes into account not only observation errors, but also errors from the measurement matrix of the variables. In this work, the TLS problem is transformed to finding the ground state of a Hamiltonian matrix. We propose quantum algorithms for solving this problem based on quantum simulation of resonant transitions. Our algorithms can achieve at least polynomial speedup over the known classical algorithms. (Source: Physics Letters A)Physics Letters AjournalsFri, 26 Apr 2019 07:39:29 +0100690075738Gauge-free electromagnetic gyrokinetic theory
https://medworm.com/689765437/gauge-free-electromagnetic-gyrokinetic-theory/
Publication date: Available online 23 April 2019Source: Physics Letters AAuthor(s): J.W. Burby, A.J. BrizardAbstractA new gauge-free electromagnetic gyrokinetic theory is developed, in which the gyrocenter equations of motion and the gyrocenter phase-space transformation are expressed in terms of the perturbed electromagnetic fields, instead of the usual perturbed potentials. Gyrocenter polarization and magnetization are derived explicitly from the gyrocenter Hamiltonian, up to first order in the gyrocenter perturbation expansion. Expressions for the sources in Maxwell's equations are derived in a form that is suitable for simulation studies, as well as kinetic-gyrokinetic hybrid modeling. (Source: Physics Letters A)Physics Letters AjournalsThu, 25 Apr 2019 03:09:33 +0100689765437Simply modified GKL density classifiers that reach consensus faster
https://medworm.com/689765436/simply-modified-gkl-density-classifiers-that-reach-consensus-faster/
Publication date: Available online 23 April 2019Source: Physics Letters AAuthor(s): J. Ricardo G. MendonçaAbstractThe two-state Gacs-Kurdyumov-Levin (GKL) cellular automaton has been a staple model in the study of complex systems due to its ability to classify binary arrays of symbols according to their initial density. We show that a class of modified GKL models over extended neighborhoods, but still involving only three cells at a time, achieves comparable density classification performance but in some cases reach consensus more than twice as fast. Our results suggest the time to consensus (relative to the length of the CA) as a complementary measure of density classification performance. (Source: Physics Letters A)Physics Letters AjournalsThu, 25 Apr 2019 03:09:33 +0100689765436Finite-time synchronization of memristor-based complex-valued neural networks with time delays
https://medworm.com/689765435/finite-time-synchronization-of-memristor-based-complex-valued-neural-networks-with-time-delays/
Publication date: Available online 23 April 2019Source: Physics Letters AAuthor(s): Kaili Sun, Song Zhu, Yongchang Wei, Xiaoke Zhang, Fei GaoAbstractThis paper deals with the problem of finite-time synchronization of memristor-based complex-valued neural networks (MCVNNs) with time delays. Based on the theory of differential inclusions with discontinuous right-hand side, we establish a new algebraic criterion of the finite-time synchronization of memristor-based complex-valued neural networks with time delays. The obtained theoretical results complement and improve some existing achievements in the real number field. Meanwhile, the obtained sufficient condition is conducive to qualitative analysis for some complex-valued nonlinear delayed systems. In the end, the conclusion is substantiate...Physics Letters AjournalsThu, 25 Apr 2019 03:09:33 +0100689765435A novel dynamic model on power failure propagation and its application to load shedding optimization
https://medworm.com/689765434/a-novel-dynamic-model-on-power-failure-propagation-and-its-application-to-load-shedding-optimization/
Publication date: Available online 23 April 2019Source: Physics Letters AAuthor(s): Shihao Nie, Li Ding, Mingyu Huang, Ping HuAbstractIn this letter, we proposed a novel individual-based dynamical model to study failure propagation in power system. In this model, a transmission line fails with a probability related to additional load transferred by other failed lines, where load upon failure of power lines is based on global and equal redistribution. Besides, the line recovers with a certain probability, and the failure levels of lines is depicted as a probability rather than a Boolean value subject to the mean-field theory. Based on this model, the outbreak threshold of the power system was analyzed. We gave the mathematical expression of the threshold for the outbreak of power failure sc...Physics Letters AjournalsThu, 25 Apr 2019 03:09:33 +0100689765434Investigation of velocity overshoot behavior in p-i-n GaAs semiconductor: The contribution of internal electric field
https://medworm.com/689765433/investigation-of-velocity-overshoot-behavior-in-p-i-n-gaas-semiconductor-the-contribution-of-intern/
Publication date: Available online 23 April 2019Source: Physics Letters AAuthor(s): Nguyen Phuoc The, Ho Khac HieuAbstractIn this work, we present the investigation of the velocity overshoot behavior in p-i-n GaAs semiconductor based on the ensemble Monte Carlo simulations. Our simulations with high-resolution of time and spatial show that the velocity overshoot effect is originated from internal electric field caused by the difference of carrier density. And this effect is dependent not only on the carrier density but also on temperature. Furthermore, we have observed the velocity relaxation effect which was not recognized before because the external electric field is too high comparing to the internal electric field in semiconductor. We point out that the velocity relaxation can be seen ...Physics Letters AjournalsThu, 25 Apr 2019 03:09:33 +0100689765433Flux modulated flat band engineering in square-kagomé ladder network
https://medworm.com/689765432/flux-modulated-flat-band-engineering-in-square-kagom-ladder-network/
Publication date: Available online 23 April 2019Source: Physics Letters AAuthor(s): Atanu Nandy, Amrita MukherjeeAbstractThe origin of non-dispersive flat band modes for a quasi-one dimensional square-kagomé ladder network is explored analytically by virtue of the real space renormalization group (RSRG) technique. A section of the eigenstates is non-diffusive i.e., localized within a cluster of sub-lattice sites partly by the destructive type of quantum interference and partly by the physical boundary created by the site with zero wave function amplitude. By making the amplitude vanish at the selective sites it becomes possible to confine the incoming excitation within the trapping cell leading to the formation of compact localized states. The effective mass of the particle becomes infini...Physics Letters AjournalsThu, 25 Apr 2019 03:09:33 +0100689765432Shocks in an electronegative plasma with Boltzmann negative ions and κ-distributed trapped electrons
https://medworm.com/689765431/shocks-in-an-electronegative-plasma-with-boltzmann-negative-ions-and-distributed-trapped-electron/
Publication date: Available online 24 April 2019Source: Physics Letters AAuthor(s): Shaukat Ali Shan, Nadia ImtiazAbstractWe derived a Schamel-Burgers equation to study the dynamics of nonlinear structures in dissipative electronegative plasma having Boltzmann negative ions and κ- distributed trapped electrons. A recently introduced Tangent hyperbolic method has been employed to get the solutions of the differential equations which contain fractional nonlinearity. The effects of different physical parameters particularly, the kinematic viscosity, the superthermality, the trapping efficiency and the electronegativity factor on the ion acoustic (IA) shock profiles have been elaborated. In case of non-dissipative electronegative plasma, the small amplitude double layers (DLs) have also been ...Physics Letters AjournalsThu, 25 Apr 2019 03:09:33 +0100689765431Microstructure, magnetic and magnetocaloric properties in magnetic-field-induced martensitic transformation Mn1−xCo1+xGe alloy ribbons
https://medworm.com/688666381/microstructure-magnetic-and-magnetocaloric-properties-in-magnetic-field-induced-martensitic-transfo/
Publication date: Available online 19 April 2019Source: Physics Letters AAuthor(s): Chicheng Ma, Qing Ge, Kai Liu, Nan Ye, Jiancheng TangAbstractThe sharp field-induced metamagnetic martensitic transformation plays a pivotal role in magnetoresponsive effects for ferromagnetic shape memory alloys (FSMAs). Homogeneous polycrystalline Mn1−xCo1+xGe alloy ribbons are prepared by using the arc-melting and melt-spinning technique in this work. The microstructure, crystalline structure, magnetic and magnetocaloric properties are studied in these ribbons. The substitution of Co for Mn reduces the structural transformation temperature, which leads to the realization of coincident magnetostructural transformation. Strikingly, a magnetic-field-induced martensitic transformation is observed in these ...Physics Letters AjournalsSat, 20 Apr 2019 22:12:31 +0100688666381Neutron emission from fracturing of granite blocks: An experimental revisitation
https://medworm.com/688347681/neutron-emission-from-fracturing-of-granite-blocks-an-experimental-revisitation/
Publication date: Available online 18 April 2019Source: Physics Letters AAuthor(s): P. Benetti, F. Boffelli, C. Marciano, A. Piazzoli, G.L. RaselliAbstractA series of experimental tests, such as those of Carpinteri et al. (2013), have been performed. The aim was to check the emission of neutrons in the fracture of Luserna granite blocks under mechanical loading, as reported by the above mentioned authors. No neutrons have been detected and some doubts have emerged on the soundness of the previous measurements. (Source: Physics Letters A)Physics Letters AjournalsFri, 19 Apr 2019 17:39:30 +0100688347681Origin of negative temperatures in systems interacting with external fields
https://medworm.com/688347680/origin-of-negative-temperatures-in-systems-interacting-with-external-fields/
Publication date: Available online 18 April 2019Source: Physics Letters AAuthor(s): Salvatore Calabrese, Amilcare PorporatoAbstractThe controversial existence of negative temperatures has stirred interesting debates that have reached the foundations of thermodynamics, including questions on the second law, the Carnot efficiency and the statistical definition of entropy. Here we show that for systems interacting with an external field, negative temperatures may arise when the interaction energy with the field is treated as a form of internal energy. We discuss how negative temperatures are avoided when using a thermodynamic formalism that accounts for the intensive and extensive variables associated to the external field. We use the paramagnetic system and a perfect gas in a gravitational f...Physics Letters AjournalsFri, 19 Apr 2019 17:39:30 +0100688347680Editors
https://medworm.com/688347655/editors/
Publication date: 23 May 2019Source: Physics Letters A, Volume 383, Issue 15Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 19 Apr 2019 17:39:30 +0100688347655Non-autonomous Hénon-Heiles system from Painlevé class
https://medworm.com/688032103/non-autonomous-hnon-heiles-system-from-painlev-class/
Publication date: Available online 17 April 2019Source: Physics Letters AAuthor(s): Maciej BłaszakAbstractWe show how to deform separable Hénon-Heiles system with isospectral Lax representation, related with the stationary flow of the 5th-order KdV, to respective non-autonomous systems of Painlevé type with isomonodromic Lax representation. (Source: Physics Letters A)Physics Letters AjournalsThu, 18 Apr 2019 12:15:27 +0100688032103Non-local quantum functions and the distributed Deutsch-Jozsa algorithm
https://medworm.com/687873772/non-local-quantum-functions-and-the-distributed-deutsch-jozsa-algorithm/
Publication date: Available online 16 April 2019Source: Physics Letters AAuthor(s): Andrei Tănăsescu, Mihai-Zicu Mina, Pantelimon George PopescuAbstractNon-local implementations of quantum gates are a vital part of quantum networks. We find an optimal non-local implementation of quantum functions, the quantum gate equivalent of a switch statement. Then, we apply this result to the Deutsch-Jozsa problem, obtaining a distributed Deutsch-Jozsa algorithm and we show the relative efficiency improvement. As an application, we find a non-cooperative game based upon the original Deutsch-Jozsa problem where a classical agent has at most a 50% probability of winning, while a quantum agent can win every time. (Source: Physics Letters A)Physics Letters AjournalsWed, 17 Apr 2019 21:39:23 +0100687873772Spin transport properties in Fe-doped graphene/hexagonal boron-nitride nanoribbons heterostructures
https://medworm.com/687873771/spin-transport-properties-in-fe-doped-graphenehexagonal-boron-nitride-nanoribbons-heterostructures/
Publication date: Available online 16 April 2019Source: Physics Letters AAuthor(s): Mei Wang, Xinxin Jiang, Xiaoteng Li, Dongmei Li, Bin Cui, Desheng LiuAbstractBy combining non-equilibrium Green's function (NEGF) with density functional theory (DFT), we systematically study the spin-related transport properties of the heterostructures composed of graphene and hexagonal boron-nitride (h-BN) when the metal Fe is doped different positions of the heterostructures interface. The results show that the heterostructures exhibit obvious spin-filtering effect (SFE) and negative differential resistance (NDR) due to the different absorbing positions of the metal Fe. And the spin filtering ratio can reach more than 90% in a specific bias voltage range. Moreover, spin-rectifying behaviors are detected ...Physics Letters AjournalsWed, 17 Apr 2019 21:39:23 +0100687873771Photocurrent in single walled carbon nanotubes
https://medworm.com/687873770/photocurrent-in-single-walled-carbon-nanotubes/
In this study, photoresponse in semiconducting single-walled carbon nanotubes is investigated using density functional theory. The photocurrent generated is found to increase with the increasing electrode voltage at a constant flux. In all models the current increases uniformly with applied voltage and maximum value of current is found in the pristine CNT model, however the magnitude of photocurrent decreases in the homogenously nitrogen and boron doped models. Moreover, the photocurrent increases with increase in flux showing photoresistive property in CNTs. The spectral peaks appear at different wavelengths in the three models paving way for wide range of applications in the futuristic optoelectronic devices. (Source: Physics Letters A)Physics Letters AjournalsWed, 17 Apr 2019 21:39:23 +0100687873770Stratification phenomenon in an inclined rheology of UCM nanomaterial
https://medworm.com/687873769/stratification-phenomenon-in-an-inclined-rheology-of-ucm-nanomaterial/
Publication date: Available online 16 April 2019Source: Physics Letters AAuthor(s): Aamir Ali, Mehvish Nazir, Muhammad Awais, Aqsa, M.Y. MalikAbstractThis investigation presents the unsteady rheology of Maxwell nanomaterial induced to flow over an inclined surface. Simultaneous effects of stratification, thermal radiation, heat source/sink and magnetic field are taken into account. Viscous dissipation and mixed convection due to concentration and temperature differences are also analyzed. The governing partial differential equations for the Maxwell nanofluid which incorporate the effects of Brownian and thermophoresis effects are simplified by using appropriate similarity transformations, and solved analytically by using homotopy analysis method (HAM). The effects of involved physical para...Physics Letters AjournalsWed, 17 Apr 2019 21:39:23 +0100687873769Vertex configuration rules to grow an octagonal Ammann–Beenker tiling
https://medworm.com/687559379/vertex-configuration-rules-to-grow-an-octagonal-ammannbeenker-tiling/
Publication date: Available online 15 April 2019Source: Physics Letters AAuthor(s): Cheng Cai, Longguang Liao, Xiujun FuAbstractBased on vertex configurations in the Ammann–Beenker tiling, we propose an algorithm for aggregation of square and rhombus tiles to generate an octagonal quasilattice, which mimics the growth process of a two-dimensional quasicrystal. Local matching rules with configuration selection are used to guide the way that tiles are joined to a cluster and form Ammann lines according to a generalized Fibonacci sequence. Our results reveal that vertex configuration selection can improve the performance of the algorithm, which provides an approach for growing a perfect octagonal quasiperiodic structure. (Source: Physics Letters A)Physics Letters AjournalsTue, 16 Apr 2019 16:39:26 +0100687559379Why cannot all divalent cations completely substitute the Pb cations of CH3NH3PbI3 perovskite?
https://medworm.com/686779978/why-cannot-all-divalent-cations-completely-substitute-the-pb-cations-of-ch3nh3pbi3-perovskite/
Publication date: Available online 12 April 2019Source: Physics Letters AAuthor(s): Denghui Ji, Shuling Wang, Hong Zhang, Huaying Wang, Buqin Zhang, Congmin Zhang, Xiuling LiAbstractOrganic-inorganic hybrid CH3NH3PbI3 perovskite has a great potential for applications in low-cost photovoltaic devices. However, the doped and substitution of Pb sites in CH3NH3PbI3 has not been widely reported. In this article, a quantum mechanical model was applied to determine why all divalent cations cannot substitute the Pb cations of CH3NH3PbI3 perovskite. The evaluation was performed by comparison the model with experimental results. On this basis, we carefully examined 42 types of cations and identified only nine kinds of cations including Ca2+, Sr2+, Sc2+, Ti2+, V2+, Y2+, Zr2+, Nb2+ and Sn2+ for doped ...Physics Letters AjournalsSat, 13 Apr 2019 16:36:25 +0100686779978Perfect spin-filtering in p-aminophenol functionalized zigzag graphene nanoribbons: The role of sp3 hybridized nitrogen
https://medworm.com/686779977/perfect-spin-filtering-in-p-aminophenol-functionalized-zigzag-graphene-nanoribbons-the-role-of-sp3-/
Publication date: Available online 12 April 2019Source: Physics Letters AAuthor(s): Zhi-Ang Jia, Xiao-Fei Li, Xinrui Cao, Xiang-Hua Zhang, Zhiyong WangAbstractCovalent functionalization of graphene is recently developed from the formation of sp3 hybridized carbon atom (sp3-C) to the sp3 hybridized nitrogen (sp3-N) at the anchoring site. Here, we investigated the electronic structures and transport properties of the zigzag graphene nanoribbons functionalized by covalently bonding of p-aminophenol (p-AP) molecule. First principles results demonstrate that the formed sp3-N plays a vital role in determining the electronic structure and transport properties of the system, resulting in a halfmetallic characteristic with a perfect spin-filtering behavior (100%). Interestingly, the performance of ...Physics Letters AjournalsSat, 13 Apr 2019 16:36:25 +0100686779977Spin-dependent transport properties of debrominated tetrabromopolyaromatic with Cu or Co doping embedded between zigzag graphene nanoribbon electrodes
https://medworm.com/686779976/spin-dependent-transport-properties-of-debrominated-tetrabromopolyaromatic-with-cu-or-co-doping-embe/
Publication date: Available online 12 April 2019Source: Physics Letters AAuthor(s): Dongde Li, Xiaojiao Zhang, Mingjun Li, Haiming Duan, Bingchu Yang, Mengqiu LongAbstractUsing density functional theory combined with non-equilibrium Green's function method, we investigate the spin-dependent transport properties of debrominated tetrabromopolyaromatic (D-TBPA) molecules embedded between zigzag graphene nanoribbon electrodes, and the effects of copper and cobalt side doping have also been considered. Our results show that the copper doping can insert new energy levels around the Fermi Level and keep spin degeneration of band structure, the cobalt doping can also induce spin splitting. The results on spin transport properties of D-TBPAs embedded into zigzag graphene nanoribbon electrodes show ...Physics Letters AjournalsSat, 13 Apr 2019 16:36:25 +0100686779976Magnetic field control of current through model graphene nanosheets
https://medworm.com/686779975/magnetic-field-control-of-current-through-model-graphene-nanosheets/
Publication date: Available online 12 April 2019Source: Physics Letters AAuthor(s): Umesh Dhakal, Dhurba RaiAbstractWe study magnetic field control of current through model graphene nanosheet junctions within the framework of the tight-binding approximation. Geometrical asymmetry in the coupling of graphene nanosheets to the contact leads emerges as one of the most important determining factors for the magnetic field control of current. The asymmetric connection split the otherwise degenerate energy levels of the structures leading to energy-resolved transmission peaks which the applied field modulates for a transmission maximum by narrowing the energy gap between the split energy levels. Also, the contact coupling strength plays a decisive role in controlling current in small structures, ...Physics Letters AjournalsSat, 13 Apr 2019 16:36:25 +0100686779975A maximum algebraic connectivity increment edge-based strategy for capacity enhancement in scale-free networks
https://medworm.com/686779974/a-maximum-algebraic-connectivity-increment-edge-based-strategy-for-capacity-enhancement-in-scale-fre/
Publication date: Available online 12 April 2019Source: Physics Letters AAuthor(s): Gang Li, Zhi Feng Hao, Han Huang, Hang Wei, Xue Ming YanAbstractIn this paper, we focus on how to improve transportation efficiency of scale-free networks via edge increments. Based on analyzing the correlation between algebraic connectivity, which is the second smallest eigenvalue of the graph Laplacian matrix, and traffic capacity, we propose an effective edge-addition strategy called maximum algebraic connectivity increment edge (MACIE). Existing approaches are based on topological structure parameters, such as path and degree of a network, which require expensive computation. Different from existing edge-addition strategies, MACIE enhances transport efficiency by maximizing algebraic connectivity, and t...Physics Letters AjournalsSat, 13 Apr 2019 16:36:25 +0100686779974Topological states in the Hofstadter model on a honeycomb lattice
https://medworm.com/686779973/topological-states-in-the-hofstadter-model-on-a-honeycomb-lattice/
Publication date: Available online 13 April 2019Source: Physics Letters AAuthor(s): Igor N. KarnaukhovAbstractWe provide a detailed analysis of a topological structure of a fermion spectrum in the Hofstadter model with different hopping integrals along the x,y,z-links (tx=t,ty=tz=1), defined on a honeycomb lattice. We have shown that the chiral gapless edge modes are described in the framework of the generalized Kitaev chain formalism, which makes it possible to calculate the Hall conductance of subbands for different filling and an arbitrary magnetic flux ϕ. At half-filling the gap in the center of the fermion spectrum opens for t>tc=2ϕ, a quantum phase transition in the 2D-topological insulator state is realized at tc. The phase state is characterized by zero energy Majorana states loc...Physics Letters AjournalsSat, 13 Apr 2019 16:36:25 +0100686779973Explosive synchronization through dynamical environment
https://medworm.com/686623966/explosive-synchronization-through-dynamical-environment/
We report the emergence of an explosive synchronization transition in the identical oscillators interacting indirectly through a network of dynamical agents. The transition from incoherent state to coherent state and vice–versa in these coupled oscillator exhibits an abrupt as well as irreversible. Such transition depends on the network topology as well as the interaction between the oscillators and dynamical agents rather than degree-frequency correlation in the network of oscillators. The occurrence of explosive synchronization is studied in details by using an appropriate order parameter for limit-cycle oscillators with respect to the different parameters like rewiring probability, average degree, and diffusion rate in dynamical agents. (Source: Physics Letters A)Physics Letters AjournalsSat, 13 Apr 2019 02:09:37 +0100686623966The geometric potential of a double-frequency corrugated surface
https://medworm.com/686623956/the-geometric-potential-of-a-double-frequency-corrugated-surface/
Publication date: Available online 11 April 2019Source: Physics Letters AAuthor(s): Wei-ran Cao, Yong-long Wang, Xiao-Lei Chen, Hua Jiang, Chang-Tan Xu, Hong-Shi ZongAbstractFor an electron confined to a surface reconstructed by double-frequency corrugations, we give the effective Hamiltonian by the formula of geometric influences, obtain an additive scalar potential induced by curvature that consists of attractive wells with different depth. The difference is generated by the multiple frequency of the double-frequency corrugation. Subsequently, we investigate the effects of geometric potential on the transmission probability, and find the resonant tunneling peaks becoming rapidly sharper and the transmission gaps being substantially widened with increasing the multiple frequency . As a po...Physics Letters AjournalsSat, 13 Apr 2019 02:09:37 +0100686623956Effective spin-2 quasi-particles at linear dispersive five-fold degenerate points with tunable topological Chern numbers
https://medworm.com/686623955/effective-spin-2-quasi-particles-at-linear-dispersive-five-fold-degenerate-points-with-tunable-topol/
Publication date: Available online 11 April 2019Source: Physics Letters AAuthor(s): Cheng Feng, Qiang Wang, S.N. Zhu, Hui LiuAbstractIn this work, which is based on spin-2 vectors and traceless spin-2 tensors, an effective Hamiltonian is constructed with a linearly dispersive five-fold degenerate point with spin-2 vector-momentum couplings. For the model without spin-2 vector-tensor coupling, the topological Chern numbers of five bands are calculated as 4, 2, 0, −2, −4. After including spin-2 vector-tensor coupling, separate topological Chern numbers are obtained for different couplings. A cubic lattice of atoms with five internal states is designed to realize two five-fold degenerate points. The Chern numbers of the bands can be changed by tuning the coupling coefficient. In this work...Physics Letters AjournalsSat, 13 Apr 2019 02:09:37 +0100686623955Monte Carlo simulation of electric conductivity for pure and doping fullerene (C60)
https://medworm.com/686312448/monte-carlo-simulation-of-electric-conductivity-for-pure-and-doping-fullerene-c60/
Publication date: Available online 10 April 2019Source: Physics Letters AAuthor(s): Zakarya Berkai, Mebarka Daoudi, Nesrine Mendil, Abderrahmane BelghachiAbstractIn this paper, we have used Monte Carlo (MC) method to simulate and study the temperature and doping effects on the electric conductivity of fullerene (C60). The results show that the band gap has reduced by the doping and the charge carrier transport is facilitated from valence band to conduction band by the temperature where is touched a 300 K. In this case, the conductivity reached a value of 4×10−7Scm−1. The electric conductivity of C60 can increase by the triphenylmethane dye crystal violet (CV) alkali metal to reach 4×10−3Scm−1 at 303 K. Our results of MC simulation have a good agreement with those extracted from l...Physics Letters AjournalsThu, 11 Apr 2019 20:15:25 +0100686312448One-dimensional structure of multi-component fine particle (dust) clouds under gravity
https://medworm.com/686312447/one-dimensional-structure-of-multi-component-fine-particle-dust-clouds-under-gravity/
Publication date: Available online 10 April 2019Source: Physics Letters AAuthor(s): Hiroo TotsujiAbstractThe structure of electrostatic potential and the distribution of fine particle (dust) clouds are analyzed in the case where we have fine particles of multiple components in plasmas under gravity. This extends the model for one-dimensional structures of fine particle cloud based on the enhanced charge neutrality in clouds to multi-species cases. Fine particles of different species are shown to form stratified clouds with simply expressed mutual separations. The results may be applied to analyze or segregate mixtures of dusts in atmospheres. (Source: Physics Letters A)Physics Letters AjournalsThu, 11 Apr 2019 20:15:25 +0100686312447Interplay of electron-electron and electron-phonon interactions in molecular junctions
https://medworm.com/686312446/interplay-of-electron-electron-and-electron-phonon-interactions-in-molecular-junctions/
Publication date: Available online 10 April 2019Source: Physics Letters AAuthor(s): Amir Eskandari-aslAbstractIn this work we consider a current carrying molecular junction with both electron-phonon and electron-electron interactions taken into account. After performing Lang-Firsov transformation and considering Markov approximations in accordance to weak coupling to the electronic leads, we obtain the master equation governing the time evolution of the reduced density matrix of the junction. The steady state of the density matrix can be used to obtain I-V characteristic of the junction in several regimes of strengths of the interactions. Our results indicate that the system can show negative differential conductance (that is, the current decreases by increasing the applied bias voltage) i...Physics Letters AjournalsThu, 11 Apr 2019 20:15:25 +0100686312446Universal transition to inactivity in global mixed coupling
https://medworm.com/686155473/universal-transition-to-inactivity-in-global-mixed-coupling/
Publication date: Available online 9 April 2019Source: Physics Letters AAuthor(s): K. Yadav, N.K. Kamal, M.D. ShrimaliAbstractThe collective dynamics of a network of nonlinear oscillators can be represented in terms of activity level of the network. We have studied a universal transition from activity to inactivity in a globally coupled network of identical oscillators. We consider mixed coupling, where some of the network elements interact through the similar variables while others with dissimilar variables. The coupling strength at which the network become inactive is inversely proportional to the ratio of number of elements coupled through similar variable to the number of elements coupled through dissimilar variables. Results are presented for the network of various globally coupled li...Physics Letters AjournalsThu, 11 Apr 2019 06:03:29 +0100686155473Few-body quantum method in a d-dimensional space
https://medworm.com/685842260/few-body-quantum-method-in-a-d-dimensional-space/
Publication date: Available online 8 April 2019Source: Physics Letters AAuthor(s): E. Garrido, A.S. Jensen, R. Álvarez-RodríguezAbstractIn this work we investigate the continuous confinement of quantum systems from three to two dimensions. Two different methods will be used and related. In the first one the confinement is achieved by putting the system under the effect of an external field. This method is conceptually simple, although, due to the presence of the external field, its numerical implementation can become rather cumbersome, especially when the system is highly confined. In the second method the external field is not used, and it simply considers the spatial dimension d as a parameter that changes continuously between the ordinary integer values. In this way the numerical effo...Physics Letters AjournalsWed, 10 Apr 2019 00:15:29 +0100685842260Editors
https://medworm.com/685842232/editors/
Publication date: 9 May 2019Source: Physics Letters A, Volume 383, Issue 14Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 10 Apr 2019 00:15:29 +0100685842232Nonclassicality in off-resonant Raman process
https://medworm.com/685060443/nonclassicality-in-off-resonant-raman-process/
Publication date: Available online 5 April 2019Source: Physics Letters AAuthor(s): Kishore Thapliyal, Jan PeřinaAbstractThe detuning parameter in experimentally feasible off-resonant Raman process is shown as a control parameter to probe and enhance the nonclassicality generated in the output of the process. Specifically, the normal characteristic function is obtained for the process as a function of detuning parameters in Stokes and anti-Stokes generation processes using more general solution than the conventional short-time solution under complete quantum treatment, which remains in the multimode Gaussian form. Single- and two-mode squeezing and antibunching as well as intermodal entanglement are reported in terms of experimentally accessible quantum noise fluctuations considering eithe...Physics Letters AjournalsSat, 06 Apr 2019 23:42:35 +0100685060443Compressibility of random walker trajectories on growing networks
https://medworm.com/685060442/compressibility-of-random-walker-trajectories-on-growing-networks/
Publication date: Available online 6 April 2019Source: Physics Letters AAuthor(s): Robert J.H. Ross, Charlotte Strandkvist, Walter FontanaAbstractWe find that the simple coupling of network growth to the position of a random walker on the network generates a traveling wave in the probability distribution of nodes visited by the walker. We argue that the entropy of this probability distribution is bounded as the network size tends to infinity. This means that the growth of a space coupled to a random walker situated in it constrains its dynamics to a set of typical random walker trajectories, and walker trajectories inside the growing space are compressible. (Source: Physics Letters A)Physics Letters AjournalsSat, 06 Apr 2019 23:42:35 +0100685060442Ferromagnetic titanium doped black phosphorus
https://medworm.com/684742783/ferromagnetic-titanium-doped-black-phosphorus/
Publication date: Available online 2 April 2019Source: Physics Letters AAuthor(s): Xiaohong Jiang, Xinwei Zhang, Zhenghe Hua, Dongqiang Han, Wenhua Zhao, Zhihe Wang, Shaoguang YangAbstractDiluted magnetic semiconductor (DMS) and layered material black phosphorus (BP) are two kinds of important materials. In this manuscript, it was reported on the observation of ferromagnetism in Ti-doped BP synthesized by high pressure method. Clear hysteresis loops were observed at room temperature. The Curie temperature was deduced to be 130-140 K. Transport studies showed us temperature dependent positive-to-negative magnetoresistance (MR) transition with the 40% MR effect at 30 K under the magnetic field of 50 kOe. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Apr 2019 18:12:26 +0100684742783Luminescence property improvement of Ba2LaSbO6:Mn4+ phosphor by using Dy3+ or H3BO3
https://medworm.com/684742777/luminescence-property-improvement-of-ba2lasbo6mn4-phosphor-by-using-dy3-or-h3bo3/
Publication date: Available online 4 April 2019Source: Physics Letters AAuthor(s): Renping Cao, Longxiang Xu, Yaqin Ran, Xinyan Lv, Siling Guo, Hui Ao, Ting Chen, Zhiyang LuoAbstractBa2LaSbO6:Mn4+, Ba2LaSbO6:Mn4+, Dy3+, and Ba2LaSbO6:Mn4+, H3BO3 phosphors are synthesized in the air by high temperature solid state reaction method. The particle sizes and sintering degree of Ba2LaSbO6:Mn4+ phosphor may be changed by doping Dy3+ ion and H3BO3. When the small amount of Dy3+ ion and H3BO3 are codoped, the emission intensity of Ba2LaSbO6:Mn4+ phosphor can be enhanced 1.2–1.3 times and the quantum efficiency of Ba2LaSbO6:Mn4+ phosphor can be improved. The lifetime of Ba2LaSbO6:Mn4+ phosphor may be changed by doping Dy3+ ion and H3BO3. The experimental results are valuable in research of luminesc...Physics Letters AjournalsFri, 05 Apr 2019 18:12:26 +0100684742777Construction of noisy bound entangled states and the range criterion
https://medworm.com/684742776/construction-of-noisy-bound-entangled-states-and-the-range-criterion/
Publication date: Available online 4 April 2019Source: Physics Letters AAuthor(s): Saronath Halder, Ritabrata SenguptaAbstractIn this work we consider bipartite noisy bound entangled states with positive partial transpose, that is, such a state can be written as a convex combination of an edge state and a separable state. In particular, we present schemes to construct distinct classes of noisy bound entangled states which satisfy the range criterion. As a consequence of the present study we also identify noisy bound entangled states which do not satisfy the range criterion. All of the present states are constituted by exploring different types of product bases. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Apr 2019 18:12:26 +0100684742776Prediction of interface states in liquid surface waves with one-dimensional modulation
https://medworm.com/684742775/prediction-of-interface-states-in-liquid-surface-waves-with-one-dimensional-modulation/
Publication date: Available online 4 April 2019Source: Physics Letters AAuthor(s): Xi Shi, Yong Sun, Chunhua Xue, Xinhua HuAbstractWe theoretically study the interface states of liquid surface waves propagating over the heterojunctions formed by a bottom with one-dimensional periodic undulations. By considering the periodic structure as a homogeneous one, our systematic study shows that the signs of the effective depth and gravitational acceleration are opposite within the band gaps whether the structure is symmetric or not. Those effective parameters can be used to predict the interface states which could amplify the amplitudes of liquid surface waves. These phenomena provide new opportunities to control the localization of water-wave energy. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Apr 2019 18:12:26 +0100684742775Explosive synchronization in through dynamical environment
https://medworm.com/684742774/explosive-synchronization-in-through-dynamical-environment/
We report the emergence of an explosive synchronization transition in the identical oscillators interacting indirectly through a network of dynamical agents. The transition from incoherent state to coherent state and vice–versa in these coupled oscillator exhibits an abrupt as well as irreversible. Such transition depends on the network topology as well as the interaction between the oscillators and dynamical agents rather than degree-frequency correlation in the network of oscillators. The occurrence of explosive synchronization is studied in details by using an appropriate order parameter for limit-cycle oscillators with respect to the different parameters like rewiring probability, average degree, and diffusion rate in dynamical agents. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Apr 2019 18:12:26 +0100684742774Spin polarization and temperature dependence of electron effective mass in quantum wires
https://medworm.com/684742773/spin-polarization-and-temperature-dependence-of-electron-effective-mass-in-quantum-wires/
Publication date: Available online 4 April 2019Source: Physics Letters AAuthor(s): Le Van-Tan, Trieu Van Thang, Nguyen Duy Vy, Huy Thien CaoAbstractThe electron effective mass in GaAs quantum wires has been estimated by using a full dynamical random-phase approximation to examine its properties versus spin polarization, temperature, and carrier density. A decrease of mass with spin polarization is seen. The minority mass increases with the polarization while the majority mass decreases and this behaviour is seen for all densities. A maximal enhancement of mass at moderate temperature around 25 K is also presented. These calculations show a qualitative consistence with results in two-dimensional systems and help to control the electronic transport in quantum wires. (Source: Physics Letters ...Physics Letters AjournalsFri, 05 Apr 2019 18:12:26 +0100684742773Variational approximations of soliton dynamics in the Ablowitz-Musslimani nonlinear Schrödinger equation
https://medworm.com/684426238/variational-approximations-of-soliton-dynamics-in-the-ablowitz-musslimani-nonlinear-schrdinger-equ/
Publication date: Available online 3 April 2019Source: Physics Letters AAuthor(s): Rahmi Rusin, Rudy Kusdiantara, Hadi SusantoAbstractWe study the integrable nonlocal nonlinear Schrödinger equation proposed by Ablowitz and Musslimani, that is considered as a particular example of equations with parity-time (PT) symmetric self-induced potential. We consider dynamics (including collisions) of moving solitons. Analytically we develop a collective coordinate approach based on variational methods and examine its applicability in the system. We show numerically that a single moving soliton can pass the origin and decay or be trapped at the origin and blows up at a finite time. Using a standard soliton ansatz, the variational approximation can capture the dynamics well, including the finite-time...Physics Letters AjournalsThu, 04 Apr 2019 13:03:32 +0100684426238Band gap tuning of defective silicon carbide nanotubes under external electric field: Density functional theory
https://medworm.com/684426237/band-gap-tuning-of-defective-silicon-carbide-nanotubes-under-external-electric-field-density-functi/
Publication date: Available online 3 April 2019Source: Physics Letters AAuthor(s): Jamal A. TallaAbstractWe have theoretically investigated the effect of applying longitudinal and transverse electric field on silicon carbide nanotubes with different orientations of Stone Wales defects. We found that each type of Stone Wales defects maintained different formation energy. We have also successfully proved that the orientation of Stone Wales defects in silicon carbide nanotubes response quite differently upon applying external electric field, whereas, two important and interesting phenomena were observed. First, the semiconductor-metal phase transition occurred in silicon carbide nanotubes as well as the three types of Stone Wales defects. However, clear band gap variations were observed in al...Physics Letters AjournalsThu, 04 Apr 2019 13:03:32 +0100684426237Stabilization of trapless Bose-Einstein condensates without any management
https://medworm.com/684426236/stabilization-of-trapless-bose-einstein-condensates-without-any-management/
Publication date: Available online 3 April 2019Source: Physics Letters AAuthor(s): Tamilthiruvalluvar Ramakrishnan, Sabari SubramaniyanAbstractIn higher dimensions, so far, both attractive and repulsive trapless Bose-Einstein condensates (BECs) have been stabilized with the help of temporal or spatial management of the two-body contact interaction. However, in the absence of nonlinear management, up to now, there is no model to stabilize the repulsive, trapless BECs at higher dimensions. Hence, in the present study, we tried to stabilize the same and achieved with help of the interplay between three-body and higher-order interactions. In addition, we show that there is an enhancement of the stability of attractive, trapless BECs due to the inclusion of the higher-order interaction along wi...Physics Letters AjournalsThu, 04 Apr 2019 13:03:32 +0100684426236Enhancement of nanogripper performance by using soft material coating
https://medworm.com/684426235/enhancement-of-nanogripper-performance-by-using-soft-material-coating/
Publication date: Available online 3 April 2019Source: Physics Letters AAuthor(s): Hadi Ghattan Kashani, Mohammad Hossein Ghajar, Masoud ShariatPanahi, Sadegh SadeghzadehAbstractNanogrippers have been widely studied for their ability of grasping and manipulating nanoparticles and their capability to be utilized inside SEM, however, due to their very small dimensions, nanogrippers still have widespread complexity in controlling and grasping nanoparticles. In macro grippers, soft materials are used at the surface of end-effectors to reduce the probability of particles damaging, while in nanogrippers, there are limited choices for the nanogrippers and their end-effectors because of manufacturing constraints.In this research, to investigate the behavior of nanoparticles during grasping by end-...Physics Letters AjournalsThu, 04 Apr 2019 13:03:32 +0100684426235Ferromagnetic titanium doped black phosphorous
https://medworm.com/684267521/ferromagnetic-titanium-doped-black-phosphorous/
Publication date: Available online 2 April 2019Source: Physics Letters AAuthor(s): Xiaohong Jiang, Xinwei Zhang, Zhenghe Hua, Dongqiang Han, Wenhua Zhao, Zhihe Wang, Shaoguang YangAbstractDiluted magnetic semiconductor (DMS) and layered material black phosphorous (BP) are two kinds of important materials. In this manuscript, it was reported on the observation of ferromagnetism in Ti-doped BP synthesized by high pressure method. Clear hysteresis loops were observed at room temperature. The Curie temperature was deduced to be 130-140 K. Transport studies showed us temperature dependent positive-to-negative magnetoresistance (MR) transition with the 40% MR effect at 30 K under the magnetic field of 50 kOe. (Source: Physics Letters A)Physics Letters AjournalsWed, 03 Apr 2019 22:39:33 +0100684267521A simple, analytic solution of the semiclassical Rabi model in the red-detuned regime
https://medworm.com/684267520/a-simple-analytic-solution-of-the-semiclassical-rabi-model-in-the-red-detuned-regime/
Publication date: Available online 2 April 2019Source: Physics Letters AAuthor(s): L.O. CastañosAbstractWe consider the semiclassical Rabi model in the large, red-detuned regime. Using the method of multiple-scales we obtain a simple, analytic, and approximate solution that describes the evolution of the system accurately for long times and for arbitrary values of the qubit-field coupling. It is used to characterize the probability to find the qubit in the excited state and the trajectory of the associated Bloch vector. Finally, we present physical situations where the results can be applied. (Source: Physics Letters A)Physics Letters AjournalsWed, 03 Apr 2019 22:39:33 +0100684267520Density–driven superfluid transition of the constrained bosons on a lattice
https://medworm.com/684110997/densitydriven-superfluid-transition-of-the-constrained-bosons-on-a-lattice/
Publication date: Available online 1 April 2019Source: Physics Letters AAuthor(s): T.K. KopećAbstractWe formulate the Landau theory and study its consequences for lattice bosons, which are stabilized by a three-body on-site constraint. This is relevant for experiments with cold atoms in optical lattices, where the presence of three-body dissipative loss processes renders the occupation number n for bosons on short timescales effectively constrained to n≤2. We elaborate on the Landau free energy expansion resulting from the Hamiltonian of bosons in the restricted Hilbert space, and present the phase diagram of the constrained Bose lattice gas. (Source: Physics Letters A)Physics Letters AjournalsWed, 03 Apr 2019 08:12:21 +0100684110997Resonance studies using the contour deformation method in the complex momentum plane
https://medworm.com/684110996/resonance-studies-using-the-contour-deformation-method-in-the-complex-momentum-plane/
Publication date: Available online 1 April 2019Source: Physics Letters AAuthor(s): Yu Kun Yang, Yong Wu, Yi Zhi Qu, Jian Guo Wang, R.K. Janev, Song Bin ZhangAbstractA contour deformation method (CDM) in the complex momentum plane has been successfully extended and implemented to probe resonances in atomic and molecular systems. Specifically, solution of the Schrödinger equation is performed in momentum space with momentum deformed on a contour in the complex plane. The bound, resonant, and complex continuum states could be directly revealed from the eigenvalues of the Schrödinger equation in the complex momentum plane. The calculations of shape resonances in electron scattering with Na+ in Debye plasmas (one channel), and in the charge transfer process H−(1s2)+Li(1s22s) (12Σ+) →H(1s...Physics Letters AjournalsWed, 03 Apr 2019 08:12:21 +0100684110996Thermodynamics of Wignons
https://medworm.com/684110995/thermodynamics-of-wignons/
Publication date: Available online 1 April 2019Source: Physics Letters AAuthor(s): Won Sang Chung, Hassan Hassanabadi, Sepideh SargolzaeiporAbstractIn this paper, we consider the particle obeying the Wigner algebra which we call a Wignon. First, we study the single mode Wignon algebra and its representation. Then, the Hamiltonian of Wignon in the supersymmetric quantum mechanics is derived. Next, some application of Wignon thermodynamics as typical example, the Non-interacting Wignon gas, the Black body radiation and Debye model are studied in statistical mechanics and the effects of Wigner parameter in the problems on the specific heat of Non-interacting Wignon gas and the energy density of Black body radiation are calculated. Finally, we introduced the grand canonical approach for two im...Physics Letters AjournalsWed, 03 Apr 2019 08:12:21 +0100684110995Spin-resolved transport properties of DNA base multi-functional electronic devices
https://medworm.com/683160727/spin-resolved-transport-properties-of-dna-base-multi-functional-electronic-devices/
Publication date: Available online 29 March 2019Source: Physics Letters AAuthor(s): Yong Zhang, Shi-Zhang Chen, Zhong-Xiang Xie, Xia Yu, Yuan-Xiang Deng, Xiao-Hua Chen, Feng NingAbstractBy using density functional theory in combination with non-equilibrium Green's function method, we have investigated the spin-polarized electronic transport properties of four DNA base devices, namely, adenine (A), cytosine (C), guanine (G) and thymine (T). The results show the spin-polarized transport properties can be effectively regulated by adopting different bases, and thymine based device can exhibit high-efficiency spin-filtering, negative differential resistance, spin rectifying behaviors and switching effect by tuning the external magnetic field. We find that the variation in the degree of localiza...Physics Letters AjournalsSat, 30 Mar 2019 17:03:29 +0100683160727Slow light performance enhancement of graphene-based photonic crystal waveguide
https://medworm.com/683160726/slow-light-performance-enhancement-of-graphene-based-photonic-crystal-waveguide/
Publication date: Available online 29 March 2019Source: Physics Letters AAuthor(s): X. Guo, X. Wu, H. Cui, F. Yang, J. ZhouAbstractWe propose a graphene-based photonic crystal (PC) slow light waveguide, which is realized by creating periodical air holes in a silicon layer to achieve spatially varying chemical potentials of graphene. The structure is optimized around 30 THz, and a large group index of 166.6 is obtained, with a very low propagation loss of −2.1 dB/um. The corresponding normalized delay-bandwidth product reaches as high as 4.00. Furthermore, the slow light performance can be dynamically tuned by changing a bias voltage. The center frequency of the slow light waveguide can be tuned between 19.1 THz and 27.4 THz. Our results suggest that graphene-based PC structures are very ...Physics Letters AjournalsSat, 30 Mar 2019 17:03:29 +0100683160726Cooling of Al-Cu-Fe-Cr-Ni high entropy alloy with different size
https://medworm.com/683160725/cooling-of-al-cu-fe-cr-ni-high-entropy-alloy-with-different-size/
Publication date: Available online 29 March 2019Source: Physics Letters AAuthor(s): Cuiming Tang, Pinyun Ren, Xiaoxu ChenAbstractCooling rate is critical in synthesizing nanoparticles (NPs), which determines the microstructure and the corresponding mechanical, thermal and electrical properties. This research, as the most initiative one, studies microstructure formation of three different sized high entropy alloy (HEA) NPs under three different cooling rates, employing molecular dynamics (MD). Through analysis of potential energy, “common neighbor analysis”, radial distribution function, and also the mean square displacement, it is found that phase transition temperature is independent of HEA NP size, and as cooling rate decrease, more amorphous atoms transform to fcc and hcp orders, wh...Physics Letters AjournalsSat, 30 Mar 2019 17:03:29 +0100683160725Stabilization of Lagrange points in circular restricted three-body problem: A port-Hamiltonian approach
https://medworm.com/683160724/stabilization-of-lagrange-points-in-circular-restricted-three-body-problem-a-port-hamiltonian-appro/
Publication date: Available online 29 March 2019Source: Physics Letters AAuthor(s): Chang Liu, Lu DongAbstractCurrent station keeping strategies target the periodic orbits around the unstable Lagrange points. These control strategies are based on the Circular Restricted Three-Body Problem (CRTBP) linearized around an equilibrium point and cannot ensure global stability. In this paper, we use the port-Hamiltonian approach to reformulate the CRTBP with input, which preserves the original nonlinear dynamics. Designing a control strategy based on energy shaping and dissipation injection, we obtain the closed-loop Hamiltonian as the candidate of Lyapunov function, which guarantees asymptotic stability. The control strategy designed here is successfully applied to the stabilization of Lagrange p...Physics Letters AjournalsSat, 30 Mar 2019 17:03:29 +0100683160724Modeling fatigue of ascending stair evacuation with modified fine discrete floor field cellular automata
https://medworm.com/682687400/modeling-fatigue-of-ascending-stair-evacuation-with-modified-fine-discrete-floor-field-cellular-auto/
Publication date: Available online 27 March 2019Source: Physics Letters AAuthor(s): Zhijian Fu, Xingzhou Zhan, Lin Luo, Andreas Schadschneider, Junmin ChenAbstractFatigue even increases the complexity of the pedestrian dynamics which is regarded as a kind of nonlinear system, and might have a significant negative impact on the crowd evacuation. However, it has never been investigated completely and properly. Thus, the fine discrete floor field cellular automata model is modified by integrating the fatigue function to explore the influence of fatigue on the crowd ascending evacuation. The simulation fits well with the empirical data and the observations quantitatively and qualitatively, indicating the model captures the main features of evacuation considering fatigue impact. As a prediction...Physics Letters AjournalsThu, 28 Mar 2019 22:12:32 +0100682687400Optical emission behaviors of C, Al, Ti, Fe, Cu, Mo, Ag, Ta, and W wire explosions in gaseous media
https://medworm.com/682369736/optical-emission-behaviors-of-c-al-ti-fe-cu-mo-ag-ta-and-w-wire-explosions-in-gaseous-media/
Publication date: Available online 26 March 2019Source: Physics Letters AAuthor(s): Ruoyu Han, Jiawei Wu, Aici QiuAbstractElectrical explosion of wires (EEW) is a promising method for nanopowders preparation and insensitive explosives ignition. Plasma radiation plays a key role in the ignition process while little attention has been paid on this phenomenon before. This letter introduces optical emission behaviors of electrical explosions for nine materials in air, Helium, and Argon with the SWE-2 platform. Experimental results indicated that the light intensity for non-refractory metals decayed rapidly after the discharge ended. In contrast, for refractory metals, the emission continued to increase and lasted for a long period after the discharge ceased. As for spectra, the emission consis...Physics Letters AjournalsWed, 27 Mar 2019 18:03:27 +0100682369736Co-thickness and oxidation states effect on magnetic anisotropy in Co/MgO heterostructure
https://medworm.com/682369735/co-thickness-and-oxidation-states-effect-on-magnetic-anisotropy-in-comgo-heterostructure/
Publication date: Available online 26 March 2019Source: Physics Letters AAuthor(s): S. NazirAbstractInterfacial magnetism and magnetic anisotropy constant (Ki) in Co/MgO heterostructure have been studied using ab-initio density functional calculations. It is found that interfacial Co spin magnetic moment shows a strong interdependence on Co-O bond lengths and a reasonable spin-polarization of ∼80% is established as a function of Co layers. Our results revealed a saturated positive (out-of-plane) Ki of +2.80 mJ/m2 at ≥12 Co layers (∼1.6 nm Co thickness), which is associated with orbital magnetic moment difference in [100] and [001] direction along with a strong hybridization between dxy and dx2−y2 orbitals through orbital angular momentum operator Lzˆ. Furthermore, it is shown that...Physics Letters AjournalsWed, 27 Mar 2019 18:03:27 +0100682369735Editors
https://medworm.com/682369704/editors/
Publication date: 24 April 2019Source: Physics Letters A, Volume 383, Issue 13Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 27 Mar 2019 18:03:27 +0100682369704Solitary density waves in the strongly coupled one component Coulomb particle structures as experimental support of the general versatility of the caustic theory
https://medworm.com/681449597/solitary-density-waves-in-the-strongly-coupled-one-component-coulomb-particle-structures-as-experime/
Publication date: Available online 22 March 2019Source: Physics Letters AAuthor(s): R. Syrovatka, V. Filinov, L. Vasilyak, V. Fortov, L. Deputatova, V. Vladimirov, V. PecherkinAbstractIn this paper we demonstrate that generation of the solitary density wave in the strongly coupled one component Coulomb system of particles confined in a long quadrupole electrodynamic Paul trap is possible, when the energy losses due to air viscosity can be compensated by the energy contribution of the altering electric fields of the trap. Results of this paper allow to identify observed solitary waves as the caustics (according to definition of the book “Catastrophe Theory” by V. I. Arnold) and can be considered as the new experimental support of the general versatility of the caustic theory in describi...Physics Letters AjournalsSun, 24 Mar 2019 04:15:34 +0100681449597Intermediate band insertion by group-IIIA elements alloying in a low cost solar cell absorber CuYSe2: A first-principles study
https://medworm.com/681449596/intermediate-band-insertion-by-group-iiia-elements-alloying-in-a-low-cost-solar-cell-absorber-cuyse2/
Publication date: Available online 22 March 2019Source: Physics Letters AAuthor(s): Jingwen Jiang, Wentong Zhou, Yang Xue, Hua Ning, Xianqing Liang, Wenzheng Zhou, Jin Guo, Dan HuangAbstractBy using first-principles calculations based on HSE06 hybrid functional, the structural, electronic, and optical properties of CuYSe2 as a low cost absorber material have been studied. Our results show that CuYSe2 is a semiconductor with indirect band gap of 1.46 eV and optical band gap of 2.00 eV. Especially, an intermediate band has been found in Ga and In alloyed CuYSe2, respectively, which can be served as a stepping stone to optical absorption on low energy photons. Therefore, Ga and In alloyed CuYSe2 with an intermediate band as a new absorber material have been proposed. (Source: Physics Letters ...Physics Letters AjournalsSun, 24 Mar 2019 04:15:34 +0100681449596Valley polarization enhancement and oscillation in asymmetric T junctions
https://medworm.com/681449595/valley-polarization-enhancement-and-oscillation-in-asymmetric-t-junctions/
Publication date: Available online 22 March 2019Source: Physics Letters AAuthor(s): Qingtian Zhang, K.S. ChanAbstractWe studied the valley dependent transport in a T junction consisting of an armchair lead and two zigzag leads. Electrons transmitted from the armchair lead to the two outgoing zigzag leads can be valley polarized. When the two outgoing leads have different widths, electrons are pushed into the wider lead and as a result, the valley polarization of the current in the narrow lead is enhanced with an oscillatory dependence on energy. The oscillation pattern is determined by the widths of the two zigzag leads. We analyzed the total local density of states of the device region of the junction and cannot find features that attribute this enhancement to quasi-bound state formation....Physics Letters AjournalsSun, 24 Mar 2019 04:15:34 +0100681449595Enhanced mobility of high-frequency discrete breathers in a monatomic chain with odd anharmonicity
https://medworm.com/681449594/enhanced-mobility-of-high-frequency-discrete-breathers-in-a-monatomic-chain-with-odd-anharmonicity/
Publication date: Available online 22 March 2019Source: Physics Letters AAuthor(s): A. Shelkan, M. Klopov, V. HizhnyakovAbstractThe mobility of high-frequency discrete breathers in monatomic chains with nonlinear interatomic potentials of the nearest neighbors is considered. It was found that the odd (cubic and fifth) anharmonicity strongly affects the mobility of breathers, sharply increasing the distance that it propagates without being trapped. It was also found that the correctly chosen fifth anharmonicity leads to an inversion of stability between the bond-centered and site-centers breathers and to the low-radiative propagation of discrete breathers along the chain. (Source: Physics Letters A)Physics Letters AjournalsSun, 24 Mar 2019 04:15:34 +0100681449594Molecular dynamics simulation of mechanical properties of nanocrystalline platinum: Grain-size and temperature effects
https://medworm.com/681449593/molecular-dynamics-simulation-of-mechanical-properties-of-nanocrystalline-platinum-grain-size-and-t/
Publication date: Available online 22 March 2019Source: Physics Letters AAuthor(s): Jiejie Li, Binbin Lu, Hongjian Zhou, Chenyao Tian, Yuehui Xian, Guoming Hu, Re XiaAbstractA series of molecular dynamics simulations has been carried out to study the mechanical properties of nanocrystalline platinum. The effects of average grain size and temperature on mechanical behaviors are discussed. The simulated uniaxial tensile results indicate the presence of a critical average grain size about 14.1 nm, for which there is an inversion of the conventional Hall-Petch relation at temperature of 300 K. The transition can be explained by a change of dominant deformation mechanism from dislocation motion for average grain size above 14.1 nm to grain boundary sliding for smaller grain size. The Young's mo...Physics Letters AjournalsSun, 24 Mar 2019 04:15:34 +0100681449593Lump, lumpoff and predictable rogue wave solutions to the (2+1)-dimensional asymmetrical Nizhnik-Novikov-Veselov equation
https://medworm.com/681135217/lump-lumpoff-and-predictable-rogue-wave-solutions-to-the-21-dimensional-asymmetrical-nizhnik-nov/
Publication date: Available online 21 March 2019Source: Physics Letters AAuthor(s): Pinxia Wu, Yufeng ZhangAbstractThis paper mainly uses Hirota bilinear form to investigate the (2+1)-dimensional asymmetrical Nizhnik-Novikov-Veselov equation. We obtain the general lump solutions and discuss its positiveness, the propagation path, amplitude and position at any time. Based on the general lump solutions, lumpoff solutions which a combination of lump solitons and stripe solitons, are also triumphantly acquired. Similarly, according to the general lump solutions, we are also consider a particular rogue wave by introducing a pair of stripe solitons, and research its predictability which include the time of the rogue wave appearance, position at time, propagation path and the maximum value of wav...Physics Letters AjournalsFri, 22 Mar 2019 23:15:32 +0100681135217Frozen entanglement and quantum correlations of one-parameter qubit−qutrit states under classical noise effects
https://medworm.com/681135216/frozen-entanglement-and-quantum-correlations-of-one-parameter-qubitqutrit-states-under-classical-/
Publication date: Available online 21 March 2019Source: Physics Letters AAuthor(s): Martin Tchoffo, Arthur Tsamouo Tsokeng, Odette Melachio Tiokang, Pernel Nguenang Nganyo, Lukong Cornelius FaiAbstractWe provide a detailed analysis of the dynamics of entanglement and quantum correlations for one-parameter qubit-qutrit states under independent or common classical noises influence. Namely the static noise, the Ornstein-Uhlenbeck (OU) noise and the random telegraph noise. Independently of the intrinsic features of the noises, entanglement measured by negativity and quantum correlations measured by measured-induced disturbance (MID) vanish after a finite time under the effects of independent noise environments. In a common environment setup, we show the existence of specific and very important...Physics Letters AjournalsFri, 22 Mar 2019 23:15:32 +0100681135216Magnetic circular dichroism and absorption spectra of I85→F55 transition in HoAl3(BO3)4 and HoFe3(BO3)4 single crystals
https://medworm.com/680820779/magnetic-circular-dichroism-and-absorption-spectra-of-i85f55-transition-in-hoal3bo34-and-hofe3/
Publication date: Available online 20 March 2019Source: Physics Letters AAuthor(s): A.V. Malakhovskii, V.V. Sokolov, I.A. Gudim, M.V. RautskiiAbstractComparative study of magnetic circular dichroism (MCD) and absorption spectra of HoAl3(BO3)4 and HoFe3(BO3)4 single crystals in the region of I85→F55 transition of the Ho3+ ion was carried out. Absorption spectra were decomposed into the Lorentz shape components and intensities of transitions were obtained. Unusually strong vibronic transitions were observed in HoAl3(BO3)4, but were not observed in HoFe3(BO3)4 that testified to the strong non diagonal vibronic interaction in HoAl3(BO3)4. The MCD spectra were analyzed in approximation of the |J,±MJ〉 wave functions of the free atom and using concept of the crystal quantum number. Peculiari...Physics Letters AjournalsThu, 21 Mar 2019 18:03:27 +0100680820779On the stability of a classical plasma
https://medworm.com/680820778/on-the-stability-of-a-classical-plasma/
Publication date: Available online 20 March 2019Source: Physics Letters AAuthor(s): M. Apostol, L.C. CuneAbstractA linearized self-consistent variational approach is employed to investigate the (thermodynamic) stability of a classical plasma (electrons and positive ions). It is shown, by using this approach, that a classical plasma, which consists of ions “dressed” with electrons, has a well-defined thermodynamics. In the strong-coupling regime the “plasma” is a solid, while, on passing to the weak-coupling regime, it becomes gradually a liquid, a non-ideal gas, and, finally, in the weak-coupling limit, it behaves as an ideal classical gas. A van der Waals-type equation is established for the plasma non-ideal gas. (Source: Physics Letters A)Physics Letters AjournalsThu, 21 Mar 2019 18:03:27 +0100680820778First digit law from Laplace transform
https://medworm.com/680820777/first-digit-law-from-laplace-transform/
Publication date: Available online 20 March 2019Source: Physics Letters AAuthor(s): Mingshu Cong, Congqiao Li, Bo-Qiang MaAbstractThe occurrence of digits 1 through 9 as the leftmost nonzero digit of numbers from real-world sources is distributed unevenly according to an empirical law, known as Benford's law or the first digit law. It remains obscure why a variety of data sets generated from quite different dynamics obey this particular law. We perform a study of Benford's law from the application of the Laplace transform, and find that the logarithmic Laplace spectrum of the digital indicator function can be approximately taken as a constant. This particular constant, being exactly the Benford term, explains the prevalence of Benford's law. The slight variation from the Benford term leads...Physics Letters AjournalsThu, 21 Mar 2019 18:03:27 +0100680820777Exact analytical results for density profile in Fourier space and elastic scattering function of a rotating harmonically confined ultra-cold Fermi gas
https://medworm.com/680820776/exact-analytical-results-for-density-profile-in-fourier-space-and-elastic-scattering-function-of-a-r/
Publication date: Available online 20 March 2019Source: Physics Letters AAuthor(s): S. Medjedel, K. BencheikhAbstractIn this paper, the system dealt with consisting of an ultra-cold neutral spin-polarized Fermi gas undergoing rotation (or in the so-called synthetic magnetic field) trapped by an anisotropic harmonic potential in a two and three-dimensional space at zero temperature. Using the so-called Bloch propagator as a tool, we derive exact closed-form expressions for particle density in Fourier space which are valid for an arbitrary particle number confined by a two and three-dimensional rotating anisotropic harmonic trap. Numerical illustrations and discussions are presented. The results can be easily generalized at finite temperatures. The crossover from two-dimensional to the one-d...Physics Letters AjournalsThu, 21 Mar 2019 18:03:27 +0100680820776A new bifurcation in non-smooth continuous system inducing semi-limit cycle
https://medworm.com/680820775/a-new-bifurcation-in-non-smooth-continuous-system-inducing-semi-limit-cycle/
This study enriches the knowledge of bifurcation analysis for non-smooth dynamical systems. (Source: Physics Letters A)Physics Letters AjournalsThu, 21 Mar 2019 18:03:27 +0100680820775A new lattice hydrodynamic model accounting for the traffic interruption probability on a gradient highway
https://medworm.com/680820774/a-new-lattice-hydrodynamic-model-accounting-for-the-traffic-interruption-probability-on-a-gradient-h/
Publication date: Available online 20 March 2019Source: Physics Letters AAuthor(s): Qingying Wang, Rongjun Cheng, Hongxia GeAbstractIn this paper, a novel lattice hydrodynamic model is presented by accounting for the traffic interruption probability on a gradient highway. The stability condition can be obtained by the use of linear analysis. Linear analysis demonstrates that the traffic interruption probability and the slope will affect the stability region. Through nonlinear analysis, the mKdV equation is derived to describe the phase transition of traffic flow. Furthermore, the numerical simulation is carried out, and the results are consistent with the analytical results. Numerical results demonstrate that the traffic flow can be efficiently improved by accounting for the traffic interr...Physics Letters AjournalsThu, 21 Mar 2019 18:03:27 +0100680820774A broadband planar acoustic metamaterial lens
https://medworm.com/680664459/a-broadband-planar-acoustic-metamaterial-lens/
Publication date: Available online 19 March 2019Source: Physics Letters AAuthor(s): Hui Yuan Dong, Jin Wang, Gang Yong Song, Wen Xuan Tang, Qiang ChengAbstractBased on quasi-conformal mapping approach, we propose a two-dimensional broadband and low-loss planar lens in the acoustic regime, which can be realized using gradient-index sub-wavelength artificial structures with hard boundary. In this design, QCM is employed in the acoustic regime to convert a parabolic form into a planar one, which makes the resultant material approximately isotropic through minimizing the anisotropic factor. It is found that the planar lens can show the same performance as its parabolic counterparts over a broadband range of frequency. Moreover, the lens is fabricated via 3D printing technology and measured exp...Physics Letters AjournalsThu, 21 Mar 2019 03:12:30 +0100680664459Equal heartbeat intervals and their effects on the nonlinearity of permutation-based time irreversibility in heart rate
https://medworm.com/680351118/equal-heartbeat-intervals-and-their-effects-on-the-nonlinearity-of-permutation-based-time-irreversib/
Publication date: Available online 7 March 2019Source: Physics Letters AAuthor(s): Wenpo Yao, Wenli Yao, Jun WangAbstractThe association of equal heartbeat intervals with cardiac conditions and the effect of the equality on permutation-based time irreversibility are investigated in this paper. We measure the distributions of equal heartbeat intervals under three conditions, namely congestive heart failure (CHF), healthy young and elderly, whose time irreversibility is detected by measuring the probabilistic difference between permutations instead of raw vectors. We demonstrate that heartbeats contain high rates of equal states, particularly the CHF with around 20% equalities, and the distributions of equal values discriminate the heartbeats at very short data length. The CHF have more equa...Physics Letters AjournalsTue, 19 Mar 2019 21:40:20 +0100680351118A new method for finding cycles by semilinear control
https://medworm.com/680351107/a-new-method-for-finding-cycles-by-semilinear-control/
Publication date: Available online 18 March 2019Source: Physics Letters AAuthor(s): Dmitriy Dmitrishin, Ivan Skrinnik, Goran Lesaja, Alex StokolosAbstractIn the paper two new results that prove typically real and local univalent properties of certain class of rational functions in the unit disc D are presented. They provide a theoretical justification of a new method for finding periodic solutions of the discrete vector dynamical systems. The main goal of the paper is to propose and investigate the two-delays generalization of the scheme introduced by Ö. Morgül. The analysis shows that the coefficients in the proposed method can be chosen in a way that improves the admissible range of parameters. The method is elementary and easy to implement. Furthermore, numerical experiments with seve...Physics Letters AjournalsTue, 19 Mar 2019 21:40:20 +0100680351107Quantum communication through chains with diluted disorder
https://medworm.com/679564110/quantum-communication-through-chains-with-diluted-disorder/
Publication date: Available online 15 March 2019Source: Physics Letters AAuthor(s): P.R.S. Júnior, G.M.A. Almeida, M.L. Lyra, F.A.B.F. de MouraAbstractWe investigate a single-qubit state transfer protocol along a channel featuring diagonal diluted disorder. In the regime where the source and destination sites are weakly coupled to the channel, we report the possibility of transmitting quantum states with high fidelity as well as establishing end-to-end entanglement in that sort of configuration. We further discuss how the performance of the protocol depends upon the availability of extended states within the disordered channel. (Source: Physics Letters A)Physics Letters AjournalsSat, 16 Mar 2019 21:36:24 +0100679564110Universal quantum uncertainty relations: Minimum-uncertainty wave packet depends on measure of spread
https://medworm.com/679564109/universal-quantum-uncertainty-relations-minimum-uncertainty-wave-packet-depends-on-measure-of-sprea/
Publication date: Available online 15 March 2019Source: Physics Letters AAuthor(s): Anindita Bera, Debmalya Das, Aditi Sen(De), Ujjwal SenAbstractBased on the statistical concept of the median, we propose a quantum uncertainty relation between semi-interquartile ranges of the position and momentum distributions of arbitrary quantum states. The relation is universal, unlike that based on the mean and standard deviation, as the latter may become non-existent or ineffective in certain cases. We show that the median-based one is not saturated for Gaussian distributions in position. Instead, the Cauchy-Lorentz distributions in position turn out to be the one with the minimal uncertainty, among the states inspected, implying that the minimum-uncertainty state is not unique but depends on the mea...Physics Letters AjournalsSat, 16 Mar 2019 21:36:24 +0100679564109Composition law for the Cole-Cole relaxation and ensuing evolution equations
https://medworm.com/679564108/composition-law-for-the-cole-cole-relaxation-and-ensuing-evolution-equations/
Publication date: Available online 15 March 2019Source: Physics Letters AAuthor(s): K. Górska, A. Horzela, A. LattanziAbstractPhysically natural assumption says that any relaxation process taking place in the time interval [t0,t2], t2>t0≥0 may be represented as a composition of processes taking place during time intervals [t0,t1] and [t1,t2] where t1 is an arbitrary instant of time such that t0≤t1≤t2. For the Debye relaxation such a composition is realized by usual multiplication which claim is not valid any longer for more advanced models of relaxation processes. We investigate the composition law required to be satisfied by the Cole-Cole relaxation and find its explicit form given by an integro-differential relation playing the role of the time evolution equation. The latter leads...Physics Letters AjournalsSat, 16 Mar 2019 21:36:24 +0100679564108On the numerical solution of nonplanar dust-acoustic super rogue waves in a strongly coupled dusty plasma
https://medworm.com/679564107/on-the-numerical-solution-of-nonplanar-dust-acoustic-super-rogue-waves-in-a-strongly-coupled-dusty-p/
Publication date: Available online 15 March 2019Source: Physics Letters AAuthor(s): Salemah Almutalk, S.A. El-Tantawy, E.I. El-Awady, S.K. El-LabanyAbstractThe occurrence of cylindrical and spherical low-frequency dust-acoustic freak waves (DAFWs) in a strongly coupled dusty plasma is numerically investigated in the framework of the phenomenological generalized hydrodynamic model. The basic equations are reduced to a modified/nonplanar nonlinear Schrödinger equation (mNLSE) using a reductive perturbation method. The existing regions of instability structures have been carefully identified. For studying the propagation of rogue waves in case of nonplanar (cylindrical and spherical coordinates), the mNLSE has been solved numerically. The effects of nonplanar geometries on the basic features...Physics Letters AjournalsSat, 16 Mar 2019 21:36:24 +0100679564107Time delay induced partial death patterns with conjugate coupling in relay oscillators
https://medworm.com/679564106/time-delay-induced-partial-death-patterns-with-conjugate-coupling-in-relay-oscillators/
Publication date: Available online 15 March 2019Source: Physics Letters AAuthor(s): Amit SharmaAbstractWe investigate the dynamics of delay-coupled relay oscillators with conjugate (or dissimilar) coupling and find the partial death with the phase-flip transition. This phenomenon is quite general and occurs for the limit cycle as well as chaotic relay oscillators. In the regime of partial death, parts of the system oscillate with large amplitude, while other element stays at rest. Using the Stuart-Landau and Rössler oscillators, we demonstrate that partial amplitude death is a robust dynamical state in coupled oscillators. We also studied the mismatch delay and find different types of dynamical pattern with partial death. (Source: Physics Letters A)Physics Letters AjournalsSat, 16 Mar 2019 21:36:24 +0100679564106Editors
https://medworm.com/679564082/editors/
Publication date: 10 April 2019Source: Physics Letters A, Volume 383, Issue 12Author(s): (Source: Physics Letters A)Physics Letters AjournalsSat, 16 Mar 2019 21:36:24 +0100679564082Equiprobable unambiguous discrimination of quantum states by symmetric orthogonalisation
https://medworm.com/679089666/equiprobable-unambiguous-discrimination-of-quantum-states-by-symmetric-orthogonalisation/
Publication date: Available online 13 March 2019Source: Physics Letters AAuthor(s): D.B. Horoshko, M.M. Eskandari, S.Ya. KilinAbstractWe show that the maximal probability of equiprobable unambiguous discrimination of a set of pure quantum states is given by the minimal eigenvalue of the Gram matrix of this set. We illustrate this result with several examples important for the protocols of quantum key distribution realized with weak coherent states of light. (Source: Physics Letters A)Physics Letters AjournalsFri, 15 Mar 2019 01:15:30 +0100679089666Is an interacting ground state (pure state) v-representable density also non-interacting ground state v-representable by a Slater determinant? In the absence of degeneracy, yes!
https://medworm.com/679089665/is-an-interacting-ground-state-pure-state-v-representable-density-also-non-interacting-ground-stat/
Publication date: Available online 13 March 2019Source: Physics Letters AAuthor(s): A. GonisAbstractIt is shown that in the absence of degeneracy a density, n(r), describing the probability of finding a particle in a small volume at position, r, that is known to be pure-state v-representable in terms of the ground state of an interacting system of particles evolving under an external potential, v(r), is also pure state v-representable in terms of a single Slater determinant describing the ground state of a system of non-interacting particles under a potential, vs(r). This establishes the validity of the Kohn–Sham formalism of density functional theory. An explicit form of vs(r) is derived. We also derive the exact form of the correlation functional and the corresponding potential, μc(r)...Physics Letters AjournalsFri, 15 Mar 2019 01:15:30 +0100679089665On the dynamics of the q-deformed logistic map
https://medworm.com/677757551/on-the-dynamics-of-the-q-deformed-logistic-map/
Publication date: Available online 8 March 2019Source: Physics Letters AAuthor(s): J. Cánovas, M. Muñoz-GuillermoAbstractWe analyze the q-deformed logistic map, where the q-deformation follows the scheme inspired in the Tsallis q-exponential function. We compute the topological entropy of the dynamical system, obtaining the parametric region in which the topological entropy is positive and hence the region in which chaos in the sense of Li and Yorke exists. In addition, it is shown the existence of the so-called Parrondo's paradox where two simple maps are combined to give a complicated dynamical behavior. (Source: Physics Letters A)Physics Letters AjournalsSun, 10 Mar 2019 00:03:43 +0100677757551Equal heartbeat intervals and their effects on the nonlinearity of time irreversibility in heart rate
https://medworm.com/677442549/equal-heartbeat-intervals-and-their-effects-on-the-nonlinearity-of-time-irreversibility-in-heart-rat/
Publication date: Available online 7 March 2019Source: Physics Letters AAuthor(s): Wenpo Yao, Wenli Yao, Jun WangAbstractThe association of equal heartbeat intervals with cardiac conditions and the effect of equality on the permutation-based time irreversibility are investigated in this paper. We measure the distributions of equal heartbeat intervals under three conditions, namely congestive heart failures (CHF), healthy young and elderly, whose nonlinearity is detected by measuring the probabilistic difference between permutations instead of raw symmetric vectors. We demonstrate that heartbeats contain high rates of equal states, particularly the CHF with around 20% equalities, and the distributions of equal values discriminate the heartbeats at very short data length. The CHF have more e...Physics Letters AjournalsFri, 08 Mar 2019 19:03:35 +0100677442549Impact of chloride treatment on the physical properties of polycrystalline thin CdTe films for solar cell applications
https://medworm.com/677442548/impact-of-chloride-treatment-on-the-physical-properties-of-polycrystalline-thin-cdte-films-for-solar/
This report presents the micro-structural, opto-electrical and surface morphological properties of e-beam evaporated thin CdTe films with the activation of post-chloride treatment. The thin films having thickness 800 nm were deposited onto glass and ITO substrates subsequently processed with CdCl2 treatment at various temperatures and then subjected to different characterization tools to investigate the physical properties. The films were found to be polycrystalline in nature having a cubic phase with preferred orientation (111) up to 320 °C and completely oxidized at 470 °C while the ohmic nature of films is confirmed by I–V characteristics. The absorbance is found to be higher in the visible range and lowest transmittance is observed for film processed at 170 °C. The ...Physics Letters AjournalsFri, 08 Mar 2019 19:03:35 +0100677442548Investigations of physical aspects of spinel ABi2O4 (A=Zn, Cd) oxides via ab-initio calculations
https://medworm.com/677442547/investigations-of-physical-aspects-of-spinel-abi2o4-azn-cd-oxides-via-ab-initio-calculations/
Publication date: Available online 7 March 2019Source: Physics Letters AAuthor(s): M. Waseem, I. Mahmood, Muhammad Rashid, Irfan Qasim, A. LarefAbstractThis present study aims to unravel physical properties of spinel oxides in cubic phase represented by general empirical formula of ABi2O4 (A=Zn, Cd) using full potential lineralized augmented plane plus local orbital (LAPW+lo) method. The structural aspect of spinel oxides in cubic phase has been investigated by Perdew-Burke-Ernzerhof generalized gradient approximation (PBEsol-GGA). The thermodynamic stability of ABi2O4 is established by computing the cohesive energies. On the other hand, born stability standard which is based on Chapin's tensor analysis method revealed that the mechanical stability of the oxide compounds under consideratio...Physics Letters AjournalsFri, 08 Mar 2019 19:03:35 +0100677442547Five-body choreography on the algebraic lemniscate is a potential motion
https://medworm.com/677442546/five-body-choreography-on-the-algebraic-lemniscate-is-a-potential-motion/
Publication date: Available online 7 March 2019Source: Physics Letters AAuthor(s): Juan Carlos Lopez VieyraAbstractIn a remarkable paper of 2003 by Fujiwara et al. [1], a figure-eight three-body choreography on the algebraic lemniscate of Bernoulli was discovered. Such a choreography was found to be driven by the action of a pairwise potential V(rij), depending only on the mutual relative distances rij, i,j=1,2,3. In the present Letter we show that two different choreographies of five bodies on the same algebraic lemniscate exist and correspond to solutions of ten coupled Newton equations of motion with a pairwise interaction potential. For each choreography the explicit form of the potential is found and ten constants of motion are presented, thus, it is superintegrable. (Source: Physics ...Physics Letters AjournalsFri, 08 Mar 2019 19:03:35 +0100677442546Insight into the magnetic behavior of Sr2IrO4: A spontaneous magnetization study
https://medworm.com/676977449/insight-into-the-magnetic-behavior-of-sr2iro4-a-spontaneous-magnetization-study/
Publication date: Available online 5 March 2019Source: Physics Letters AAuthor(s): Imtiaz Noor Bhatti, A.K. PramanikAbstractSr2IrO4 is a weak ferromagnet where the spin arrangement is canted anti-ferromagnetic (AF). Moreover, the spin-structure coupling plays an important role in magnetic behavior of Sr2IrO4. In this concern the magnetization under zero applied field i.e. spontaneous magnetization would be interesting to study and would give insight into the novel magnetic behavior of Sr2IrO4. Sophisticated techniques like neutron diffraction, μSR etc has been used to understand the magnetic behavior of Sr2IrO4 under zero applied field. To understand the magnetic behavior we have performed field and temperature dependent magnetization study. The measured field and temperature dependent ma...Physics Letters AjournalsWed, 06 Mar 2019 20:36:31 +0100676977449Electronic properties of the parabolic Dirac system
https://medworm.com/676977447/electronic-properties-of-the-parabolic-dirac-system/
Publication date: Available online 5 March 2019Source: Physics Letters AAuthor(s): Chen-Huan WuAbstractWe investigate the electronic properties of the parabolic Dirac system. In the presence of magnetic field, we discuss the thermodynamical potential and the anomalous diamagnetism due to the Dirac cone, and compared to the results of linear dispersion system. We found the local density of state peaks and the Landau levels are equidistant unlike the case of linear dispersion. The integer Hall conductivity and the intrinsic Hall conductivity induced by the Berry curvature are also investigated. Considering the disorder-induced self-energy in self-consistent Born approximation, the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction (temperature-dependent), long-range scattering rate and the spe...Physics Letters AjournalsWed, 06 Mar 2019 20:36:31 +0100676977447Highly sensitive selectively coated D-shape photonic crystal fibers for surface plasmon resonance sensing
https://medworm.com/676977446/highly-sensitive-selectively-coated-d-shape-photonic-crystal-fibers-for-surface-plasmon-resonance-se/
Publication date: Available online 5 March 2019Source: Physics Letters AAuthor(s): Fengning Zha, Jinsong Li, Pengjie Sun, Hongjie MaAbstractWe propose a design for a high sensitivity plasmon resonance (SPR) sensor based on photonic crystal fiber (PCF) and analyze the sensor using finite element software (FEM). By introducing a D-shape hole instead of a circular hole in the first ring of the photonic crystal fiber, which increases the coupling effect and proficient infiltration of the sensing, resulting in enhance the performance of the sensor due to the flat structure of the D-shape hole and the homogeneous metal coating facility. We study the influence of the parameters of the D-shape hole on the sensing performance and analyze the sensor performance based on the wavelength and amplitude ...Physics Letters AjournalsWed, 06 Mar 2019 20:36:31 +0100676977446Breather solutions of a negative order modified Korteweg-de Vries equation and its nonlinear stability
https://medworm.com/676977445/breather-solutions-of-a-negative-order-modified-korteweg-de-vries-equation-and-its-nonlinear-stabili/
Publication date: Available online 5 March 2019Source: Physics Letters AAuthor(s): Jingqun Wang, Lixin Tian, Yingnan ZhangAbstractThis paper is concerned with a negative order modified Korteweg-de Vries (nmKdV) equation which is in the negative flow of the mKdV hierarchy. We construct the breather solutions by Hirota's bilinear method and derive the infinite conservation laws through the Lax pair of the nmKdV equation. By constructing a new Lyapunov function with the conservation laws, we obtain the nonlinear stability of the breather solutions. (Source: Physics Letters A)Physics Letters AjournalsWed, 06 Mar 2019 20:36:31 +0100676977445Editors
https://medworm.com/676977423/editors/
Publication date: 25 March 2019Source: Physics Letters A, Volume 383, Issue 11Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 06 Mar 2019 20:36:31 +0100676977423Quantum heat switch with multiple qubits
https://medworm.com/676660634/quantum-heat-switch-with-multiple-qubits/
Publication date: Available online 4 March 2019Source: Physics Letters AAuthor(s): Marzie Jamshidi Farsani, Rosario FazioAbstractWe further elaborate on the device proposed by Karimi et al. [15], in which coupled superconducting qubits can play the role of a quantum heat switch. In the present paper we analyze the performances of the switch if the number of qubits increases considering in details the cases of three and four qubits. To this aim we study the effect of the number of qubits on the transmitted power between baths. As the number of qubits increases, the transmitted power between baths increases as well. (Source: Physics Letters A)Physics Letters AjournalsTue, 05 Mar 2019 15:39:29 +0100676660634Further investigation of mass dimension one fermionic duals
https://medworm.com/676660633/further-investigation-of-mass-dimension-one-fermionic-duals/
Publication date: Available online 4 March 2019Source: Physics Letters AAuthor(s): J.M. Hoff da Silva, R.T. CavalcantiAbstractIn this paper we proceed into the next step of formalization of a consistent dual theory for mass dimension one spinors. This task is developed approaching the two different and complementary aspects of such duals, clarifying its algebraic structure and the so called τ−deformation. The former regards the mathematical equivalence of the recent proposed Lorentz preserving dual with the duals of algebraic spinors, from Clifford algebras, showing the consistency and generality of the new dual. Moreover, by revealing its automorphism structure, the hole of the τ−deformation and contrasting the action group orbits with other Lorentz breaking scenarios, we argue that...Physics Letters AjournalsTue, 05 Mar 2019 15:39:29 +0100676660633Multiple-scale analysis of open quantum systems
https://medworm.com/676660632/multiple-scale-analysis-of-open-quantum-systems/
Publication date: Available online 5 March 2019Source: Physics Letters AAuthor(s): D.N. Bernal-García, B.A. Rodríguez, H. Vinck-PosadaAbstractIn this work, we present a multiple-scale perturbation technique suitable for the study of open quantum systems, which is easy to implement and in few iterative steps allows us to find excellent approximate solutions. For any time-local quantum master equation, whether markovian or non-markovian, in Lindblad form or not, we give a general procedure to construct analytical approximations to the corresponding dynamical map and, consequently, to the temporal evolution of the density matrix. As a simple illustrative example of the implementation of the method, we study an atom-cavity system described by a dissipative Jaynes-Cummings model. Performing a...Physics Letters AjournalsTue, 05 Mar 2019 15:39:29 +0100676660632THz radiation generation in axially magnetized collisional pair plasma
https://medworm.com/676503035/thz-radiation-generation-in-axially-magnetized-collisional-pair-plasma/
Publication date: Available online 1 March 2019Source: Physics Letters AAuthor(s): Sheetal Punia, Hitendra K. MalikAbstractWe investigate the electron-positron plasma for terahertz radiation generation by two Dark Hollow Gaussian beams (DHGBs), which result in multifocal radiations quite useful for various modern applications. In this process, the ponderomotive force acts as a driver for the generation of terahertz field and the realistic situation of collisional plasma under the application of axial magnetic field reveals an efficient radiation generation. An appreciable efficiency of more than 2% is achieved for the process. (Source: Physics Letters A)Physics Letters AjournalsTue, 05 Mar 2019 00:15:38 +0100676503035Robust bulk states
https://medworm.com/676503034/robust-bulk-states/
Publication date: Available online 1 March 2019Source: Physics Letters AAuthor(s): C. YuceAbstractWe predict topologically robust zero energy bulk states in a disordered tight binding lattice. We explore a new kind of order and discuss that zero energy states exist in a system iff its Hamiltonian is noninvertible. We show that they are robust against any kind of disorder as long as the disordered Hamiltonian is noninvertible, too. (Source: Physics Letters A)Physics Letters AjournalsTue, 05 Mar 2019 00:15:38 +0100676503034Modeling the magnetocaloric effect of manganite using hybrid genetic and support vector regression algorithms
https://medworm.com/676503033/modeling-the-magnetocaloric-effect-of-manganite-using-hybrid-genetic-and-support-vector-regression-a/
Publication date: Available online 1 March 2019Source: Physics Letters AAuthor(s): Taoreed O. OwolabiAbstractLarge magnetocaloric effect demonstrated by manganite-based compounds has advanced the possibility of practical implementation of magnetic refrigeration technology. In order to enhance the magnetocaloric effect of manganite based compounds and to reduce the experimental stress involved in maximum magnetic entropy change (MMEC) determination, this work develops for the first time, hybrid genetic algorithm (GA) and support vector regression (SVR) models for estimating the MMEC, using the ionic radii and crystal lattice parameters as descriptors. Aside from the performance superiority of hybrid GA-SVR-Ionic model (which uses ionic radii and the concentrations of the dopants as descript...Physics Letters AjournalsTue, 05 Mar 2019 00:15:38 +0100676503033Superior dielectric properties and bandgap modulation in hydrothermally grown Gr/MgO nanocomposite
https://medworm.com/676503032/superior-dielectric-properties-and-bandgap-modulation-in-hydrothermally-grown-grmgo-nanocomposite/
Publication date: Available online 1 March 2019Source: Physics Letters AAuthor(s): Richa Bhargava, Shakeel KhanAbstractMgO nanoparticles (NPs) and Gr/MgO nanocomposite (NC) have been synthesized by hydrothermal route. X-ray diffraction (XRD) analysis confirmed the crystalline cubic phase of MgO and Gr/MgO NC. Raman spectroscopy was used to study the defects in the NCs. Electron microscopy study display spherical NPs of MgO on graphene sheets. UV-visible spectroscopy shows a red shift in the absorption band and a significant reduction in the bandgap for Gr/MgO NC. The improvements in dielectric properties of NC can be ascribed to interfacial polarization between rGO and MgO. The rGO in the NCs supports the electron transfer and improves the electrical conductivity. (Source: Physics Letters ...Physics Letters AjournalsTue, 05 Mar 2019 00:15:38 +0100676503032Classicalization of quantum state of detector by amplification process
https://medworm.com/676503031/classicalization-of-quantum-state-of-detector-by-amplification-process/
Publication date: Available online 1 March 2019Source: Physics Letters AAuthor(s): Arash Tirandaz, Farhad Taher Ghahramani, Ali Asadian, Mehdi GolshaniAbstractIt has been shown that a macroscopic system being in a high-temperature thermal coherent state can be, in principle, driven into a non-classical state by coupling to a microscopic system. Therefore, thermal coherent states do not truly represent the classical limit of quantum description. Here, we study the classical limit of quantum state of a more relevant macroscopic system, namely the pointer of a detector, after the phase-preserving linear amplification process. In particular, we examine to what extent it is possible to find the corresponding amplified state in a superposition state, by coupling the pointer to a qubit system. We...Physics Letters AjournalsTue, 05 Mar 2019 00:15:38 +0100676503031Numerical parametric study of chiral effects and group delays in Ω element based terahertz metamaterial
https://medworm.com/676342895/numerical-parametric-study-of-chiral-effects-and-group-delays-in-element-based-terahertz-metamate/
Publication date: Available online 28 February 2019Source: Physics Letters AAuthor(s): Danka B. Stojanović, Petra P. Beličev, Jelena Radovanović, Vitomir MilanovićAbstractIn this work, we have systematically studied the impact of geometric parameters on chiral effects which occur in metamaterial made of Ω elements. The analysis of group delays and electric field enhancements indicate stronger interaction between the structure and right circularly polarized waves. Calculations of optical activity and circular dichroism for different values of geometric parameters, allow us to deduce that the thickness of the wire and the gap size have large influence on these effects. On the other hand, the radius of the wire affects mainly the resonant frequency position which enables frequency tunabi...Physics Letters AjournalsFri, 01 Mar 2019 20:45:29 +0100676342895Experimental detection of qubit-ququart pseudo-bound entanglement using three nuclear spins
https://medworm.com/676342894/experimental-detection-of-qubit-ququart-pseudo-bound-entanglement-using-three-nuclear-spins/
Publication date: Available online 28 February 2019Source: Physics Letters AAuthor(s): Amandeep Singh, Akanksha Gautam, Arvind, Kavita DoraiAbstractIn this work, we experimentally created and characterized a class of qubit-ququart PPT (positive under partial transpose) entangled states using three nuclear spins on an nuclear magnetic resonance (NMR) quantum information processor. Entanglement detection and characterization for systems with a Hilbert space dimension ≥2⊗3 is nontrivial since there are states in such systems which are both PPT as well as entangled. The experimental detection scheme that we devised for the detection of qubit-ququart PPT entanglement was based on the measurement of three Pauli operators with high precision, and is a key ingredient of the protocol in detecti...Physics Letters AjournalsFri, 01 Mar 2019 20:45:29 +0100676342894A metal-semiconductor transition triggered by atomically flat zigzag edge in monolayer transition-metal dichalcogenides
https://medworm.com/676342892/a-metal-semiconductor-transition-triggered-by-atomically-flat-zigzag-edge-in-monolayer-transition-me/
Publication date: Available online 28 February 2019Source: Physics Letters AAuthor(s): Yang Ni, Yan-Dong Guo, Xiao-Hong Yan, Hong-Li Zeng, Ying Zhang, Xin-Yu Chen, Xue-Yang ShenAbstractDue to the structure of three stacked layers, monolayer transition-metal dichalcogenides (TMDs) is different from graphene. Creating atomically flat graphene-like edges in them has long been expected, which is crucial to the modulation of electronic structures in two-dimensional systems. Recently, by thermal annealing, Chen et al. [21] successfully synthesized atomically flat Mo-terminated edge in monolayer MoS2. Inspired by this, through first-principles calculations, we studied the electronic and transport properties of typical TMD monolayers with transition atom-terminated flat zigzag edges, i.e., ScS2, V...Physics Letters AjournalsFri, 01 Mar 2019 20:45:29 +0100676342892Noise-induced quasiperiodicity in a ring of unidirectionally-coupled nonidentical maps
https://medworm.com/676342891/noise-induced-quasiperiodicity-in-a-ring-of-unidirectionally-coupled-nonidentical-maps/
Publication date: Available online 28 February 2019Source: Physics Letters AAuthor(s): A.N. Pisarchik, I.A. Bashkirtseva, L.B. RyashkoAbstractTransitions from equilibrium to quasiperiodicity and from a two-cycle to a quasiperiodic regime are studied in a ring of unidirectionally-coupled nonidentical logistic maps. The former scenario is realized through a “soft” (Neimark–Sacker) bifurcation, while the latter through a “hard” (saddle-node) bifurcation. Special attention is paid on a noise-induced transition through “hard” bifurcation, where a phenomenon of structural stabilization of the quasiperiodic system near the bifurcation point is observed and analyzed in detail. (Source: Physics Letters A)Physics Letters AjournalsFri, 01 Mar 2019 20:45:29 +0100676342891An improved Hirota bilinear method and new application for a nonlocal integrable complex modified Korteweg-de Vries (MKdV) equation
https://medworm.com/676342890/an-improved-hirota-bilinear-method-and-new-application-for-a-nonlocal-integrable-complex-modified-ko/
Publication date: Available online 28 February 2019Source: Physics Letters AAuthor(s): Li Li, Chaonan Duan, Fajun YuAbstractThe Hirota bilinear method has been studied in a lot of local equations, but there are few of works to solve nonlocal equations by Hirota bilinear method. In this letter, we show that the nonlocal integrable complex modified Korteweg-de Vries (MKdV) equation admits multiple complex soliton solutions. A variety of exact solutions including the single bright soliton solutions and two bright soliton solutions are derived via constructing an improved Hirota bilinear method for nonlocal complex MKdV equation. From the gauge equivalence, we can see the difference between the solution of nonlocal integrable complex MKdV equation and the solution of local complex MKdV equatio...Physics Letters AjournalsFri, 01 Mar 2019 20:45:29 +0100676342890Su-Schrieffer-Heeger model with imaginary gauge field
https://medworm.com/676342869/su-schrieffer-heeger-model-with-imaginary-gauge-field/
Publication date: Available online 28 February 2019Source: Physics Letters AAuthor(s): Z. Oztas, N. CandemirAbstractWe consider Su-Schrieffer-Heeger (SSH) model in the presence of an imaginary gauge field. This model is non-Hermitian and has chiral symmetry. We investigate the influence of non-Hermiticity parameter on topologically trivial and nontrivial phases. We find topological edge states with real energy spectrum and obtain the topological invariant of the system. (Source: Physics Letters A)Physics Letters AjournalsFri, 01 Mar 2019 20:45:29 +0100676342869Acoustic measurements of the infinitesimal phase response curve from a sounding organ pipe
https://medworm.com/676342868/acoustic-measurements-of-the-infinitesimal-phase-response-curve-from-a-sounding-organ-pipe/
Publication date: Available online 1 March 2019Source: Physics Letters AAuthor(s): Masahiro Okada, Tokihiko Kaburagi, Isao T. TokudaAbstractThe infinitesimal phase response curve (iPRC) of an organ pipe was measured using two types of external forcing, namely, sinusoidal and pulse forcing. Although the measured iPRCs exhibited different shapes because of the difficulty in realizing ideal pulses in acoustic experiments, the spectral structures agreed between both methods. Both measurements indicated that an external sound, which matched the pipe's second resonance, could most effectively induce frequency locking. Acoustically, this may be considered as a consequence of the pipe's open end. Our study is of significant importance in understanding the characteristics of frequency locking among...Physics Letters AjournalsFri, 01 Mar 2019 20:45:29 +0100676342868Energy exchange between discrete breathers in graphane in thermal equilibrium
https://medworm.com/675804372/energy-exchange-between-discrete-breathers-in-graphane-in-thermal-equilibrium/
Publication date: Available online 27 February 2019Source: Physics Letters AAuthor(s): K.A. Krylova, J.A. Baimova, R.T. Murzaev, R.R. MulyukovAbstractGraphane is a fully hydrogenated graphene which is practically interesting for application in electronics, hydrogen storage and transportation, in nanoscale devices. As it was previously shown, the energy of a discrete breather (nonlinear localised mode) in graphane close to the value of the energy barrier at which the dehydrogenation of graphene occurs. In the present work, molecular dynamics simulation is used to investigate the possibility of energy exchange between discrete breathers in graphane in thermal equilibrium at 400 K and 600 K. In thermally equilibrated graphane, hydrogen atoms are spontaneously excited and can be considered as ...Physics Letters AjournalsThu, 28 Feb 2019 16:24:32 +0100675804372State Observer for Stochastic Resonance in Bistable System
https://medworm.com/675804371/state-observer-for-stochastic-resonance-in-bistable-system/
Publication date: Available online 27 February 2019Source: Physics Letters AAuthor(s): Jinming Liu, Jian Mao, Bin Huang, Peiguo LiuAbstractWe investigate numerically stochastic resonance variation in bistable system. Putting signals with different intensities into a bistable system, or adjusting system structural parameters for an input, will produce different motion trajectories. These trajectories contain both chaos and non-chaos parts. We classify these states according to the state of resonance and chaos, and propose a state observer. In this way, bistable system becomes an observable nonlinear system. State observer can provide us with a new perspective that is not available through conventional observation methods. These investigations contribute to nonlinear system optimization, and...Physics Letters AjournalsThu, 28 Feb 2019 16:24:32 +0100675804371Analytical derivation of the impulse response for the bounded 2-D diffusion channel
https://medworm.com/675257433/analytical-derivation-of-the-impulse-response-for-the-bounded-2-d-diffusion-channel/
Publication date: Available online 26 February 2019Source: Physics Letters AAuthor(s): Fatih Dinc, Bayram Cevdet Akdeniz, Ecda Erol, Dilara Gokay, Ezgi Tekgul, Ali Emre Pusane, Tuna TugcuAbstractThis letter focuses on the derivation of the hitting probabilities of diffusing particles absorbed by an agent in a bounded environment. In particular, we analogously consider the impulse response of a molecular communication channel in a 2-D and 3-D environment. In 2-D, the channel involves a point transmitter that releases molecules to a circular absorbing receiver that absorbs incoming molecules in an environment surrounded by a circular reflecting boundary. Considering this setup, the joint distribution of the molecules on the circular absorbing receiver with respect to time and angle is derive...Physics Letters AjournalsWed, 27 Feb 2019 12:09:27 +0100675257433Generalized effective-potential Landau theory for the two-dimensional extended Bose-Hubbard model
https://medworm.com/675257432/generalized-effective-potential-landau-theory-for-the-two-dimensional-extended-bose-hubbard-model/
Publication date: Available online 26 February 2019Source: Physics Letters AAuthor(s): Zhi Lin, Ming YangAbstractWe analytically study the quantum phase diagrams of ultracold dipolar Bose gases in an optical square lattice at zero temperature by using the generalized effective-potential Landau theory (GEPLT). For a weak nearest-neighbor repulsion, our analytical results are better than the third-order strong-coupling expansion theory calculation. In contrast to a previous quantum Monte Carlo (QMC) simulation, we analytically calculate phase transition boundaries up to the third-order hopping, which are in excellent agreement with QMC simulations for second-order phase transition. (Source: Physics Letters A)Physics Letters AjournalsWed, 27 Feb 2019 12:09:27 +0100675257432The Higgs and Hahn algebras from a Howe duality perspective
https://medworm.com/673448123/the-higgs-and-hahn-algebras-from-a-howe-duality-perspective/
Publication date: Available online 22 February 2019Source: Physics Letters AAuthor(s): Luc Frappat, Julien Gaboriaud, Luc Vinet, Stéphane Vinet, Alexei ZhedanovAbstractThe Hahn algebra encodes the bispectral properties of the eponymous orthogonal polynomials. In the discrete case, it is isomorphic to the polynomial algebra identified by Higgs as the symmetry algebra of the harmonic oscillator on the 2-sphere. These two algebras are recognized as the commutant of a o(2)⊕o(2) subalgebra of o(4) in the oscillator representation of the universal algebra U(u(4)). This connection is further related to the embedding of the (discrete) Hahn algebra in U(su(1,1))⊗U(su(1,1)) in light of the dual action of the pair (o(4),su(1,1)) on the state vectors of four harmonic oscillators. The two-dimensio...Physics Letters AjournalsSat, 23 Feb 2019 14:09:28 +0100673448123Exact classical and quantum solutions for a covariant oscillator near the black hole horizon in Stueckelberg-Horwitz-Piron theory
https://medworm.com/673448122/exact-classical-and-quantum-solutions-for-a-covariant-oscillator-near-the-black-hole-horizon-in-stue/
Publication date: Available online 22 February 2019Source: Physics Letters AAuthor(s): Davood MomeniAbstractWe found exact solutions for canonical classical and quantum dynamics for general relativity in Horwitz general covariance theory. These solutions can be obtained by solving the generalized geodesic equation and Schrödinger-Stueckelberg -Horwitz-Piron (SHP) wave equation for a simple harmonic oscillator in the background of a two dimensional dilaton black hole spacetime metric. We proved the existence of an orthonormal basis of eigenfunctions for generalized wave equation. This basis functions form an orthogonal and normalized (orthonormal) basis for an appropriate Hilbert space. The energy spectrum has a mixed spectrum with one conserved momentum p according to a quantum number n. ...Physics Letters AjournalsSat, 23 Feb 2019 14:09:28 +0100673448122Readout of a weakly coupled qubit through the use of an auxiliary mode
https://medworm.com/673448121/readout-of-a-weakly-coupled-qubit-through-the-use-of-an-auxiliary-mode/
Publication date: Available online 22 February 2019Source: Physics Letters AAuthor(s): Filippo TroianiAbstractThe dispersive coupling between a qubit and a cavity mode is widely used for performing non-destructive readout of the qubit state. In this approach, it is typically required that the dispersive strong coupling regime is achieved. Here we show that the use of an auxiliary cavity mode reduces by orders of magnitude the required value of the dispersive coupling, for a given decay rate of the cavity mode. The analysis is performed within the input-output formalism, in terms of the photon scattering matrix elements and of the signal-to-noise ratio. We derive simple analytical expressions for the optimal parameters and recover the standard single-mode result as a limiting case. The pres...Physics Letters AjournalsSat, 23 Feb 2019 14:09:28 +0100673448121Editors
https://medworm.com/673448097/editors/
Publication date: 11 March 2019Source: Physics Letters A, Volume 383, Issue 10Author(s): (Source: Physics Letters A)Physics Letters AjournalsSat, 23 Feb 2019 14:09:28 +0100673448097Boron and nitrogen co-doped graphene nanosheets for NO and NO2 gas sensing
https://medworm.com/672538810/boron-and-nitrogen-co-doped-graphene-nanosheets-for-no-and-no2-gas-sensing/
Publication date: Available online 20 February 2019Source: Physics Letters AAuthor(s): Mehdi D. EsrafiliAbstractUsing dispersion-corrected density functional theory calculations, the adsorption behavior of NO and NO2 molecules is studied over B-doped and BN co-doped graphene sheets (BCmNn-Gr; m,n=0,1,2,3 and m+n=3). To examine practical gas sensing application and selectivity, the adsorption of H2O, CO and CO2 molecules is also studied on the BCmNn-Gr surfaces. It is found that the preferred adsorption site for the adsorption of these molecules is above the B atom due to accumulation of a local positive charge. Meanwhile, the incorporation of nitrogen atoms in BCmNn-Gr makes a substantial increase in the adsorption energies of NO and NO2, mainly due to the shift in the Fermi energy and ele...Physics Letters AjournalsThu, 21 Feb 2019 14:24:28 +0100672538810Effects of sm substitution on ferroelectric domains and conductivity in bismuth ferrite ceramics
https://medworm.com/672538809/effects-of-sm-substitution-on-ferroelectric-domains-and-conductivity-in-bismuth-ferrite-ceramics/
Publication date: Available online 20 February 2019Source: Physics Letters AAuthor(s): Panithan Sriboriboon, Benjaporn Yotburut, Oradee Srikimkaew, Sartanee Suebka, Arreerat Jiamprasertboon, Santi Maensiri, Worasom KundhikanjanaAbstractThe large piezoelectric coefficient and multiferroicity of bismuth ferrite (BFO) make it an attractive candidate for lead-free ferroelectric devices. However, large leakage currents have limited broader applications. Rare-earth substitutions in BFO have been shown to improve ferroelectric and magnetic properties. In this work, we employed piezoresponse and conductive atomic force microscopy to study ferroelectric domains in Bi1-xSmxFeO3 (x = 0–0.150) grown by the co-precipitation method. The combined piezoresponse and conductivity measurements can directly...Physics Letters AjournalsThu, 21 Feb 2019 14:24:28 +0100672538809Global dynamics of a pipe conveying pulsating fluid in primary parametrical resonance: Analytical and numerical results from the nonlinear wave equation
https://medworm.com/672538808/global-dynamics-of-a-pipe-conveying-pulsating-fluid-in-primary-parametrical-resonance-analytical-an/
Publication date: Available online 20 February 2019Source: Physics Letters AAuthor(s): Qiliang Wu, Guoyuan QiAbstractThe chaotic dynamics of nonlinear waves in the harmonic-forced fluid-conveying pipe in primary parametrical resonance, is explored analytically and numerically. The multiple scale method is applied to obtain an equivalent nonlinear wave equation from the complicated nonlinear governing equation describing the fluid conveyed in a pipe. With the Melnikov method, the persistence of a heteroclinic structure is shown to be satisfied and its condition is given in functional form. Similarly, for the heteroclinic orbit, using geometric analysis, a condition function of the stable manifold is derived for the orbit to return to the stable manifold from the saddle point. The persistent...Physics Letters AjournalsThu, 21 Feb 2019 14:24:28 +0100672538808Erratum to “Harmonic balancing approach to nonlinear oscillations of a punctual charge in the electric field of charged ring” [Phys. Lett. A 373 (7) (2009) 735–740]
https://medworm.com/672177009/erratum-to-harmonic-balancing-approach-to-nonlinear-oscillations-of-a-punctual-charge-in-the-elec/
Publication date: Available online 19 February 2019Source: Physics Letters AAuthor(s): Augusto Beléndez, Klaus R. Schneider (Source: Physics Letters A)Physics Letters AjournalsWed, 20 Feb 2019 19:18:34 +0100672177009Integrated Experimental and Computational Approach for Nanoparticle Flow Analysis
https://medworm.com/672177008/integrated-experimental-and-computational-approach-for-nanoparticle-flow-analysis/
We report a new method combining computational fluid dynamics and flow experiments with customized channels to understand the transport of nanoparticles. Iron oxide nanoparticles, being highly attractive for biomedical research are chosen as model nanoparticles for the transport studies. Four different polyvinyl pyrrolidone and polyethyleneimine coated iron oxide nanoparticles of hydrodynamic sizes ranging from 45 – 178 nm were synthesized. These nanoparticles were adjusted to different target mass concentrations and ran through a bent tube to determine flow velocity and mass loss, specific to the nanoparticles. Computational predictions were made for velocity and mass loss of fully developed flow of nanoparticles through bent channel, which compared well with experimental measurements. ...Physics Letters AjournalsWed, 20 Feb 2019 19:18:34 +0100672177008Large negative differential resistance behavior in arsenene nanoribbons induced by vacant defects
https://medworm.com/672177007/large-negative-differential-resistance-behavior-in-arsenene-nanoribbons-induced-by-vacant-defects/
Publication date: Available online 19 February 2019Source: Physics Letters AAuthor(s): Wei-Hua Xiao, Fang Xie, Xiao-Jiao Zhang, Yu-Fang Chu, Jian-Ping Liu, Hai-Yan Wang, Zhi-Qiang Fan, Meng-Qiu Long, Ke-Qiu ChenAbstractWe have studied the electronic structures of arsenene nanoribbons with different edge passivations by employing first-principle calculations. Furthermore, the effects of the defect in different positions on the transport properties of arsenene nanoribbons are also investigated. We find that the band structures of arsenene nanoribbons are sensitive to the edge passivation. The current-voltage characteristics of unpassivated and O-passivated zigzag arsenene nanoribbons exhibit a negative differential resistance behavior, while such a peculiar phenomenon has not emerged in the ...Physics Letters AjournalsWed, 20 Feb 2019 19:18:34 +0100672177007Editors
https://medworm.com/669833718/editors/
Publication date: 28 February 2019Source: Physics Letters A, Volume 383, Issue 9Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 15 Feb 2019 17:24:27 +0100669833718Ab initio study of the effect of thickness and epitaxial strain on the magnetic structure of NiMn freestanding films
https://medworm.com/669291791/ab-initio-study-of-the-effect-of-thickness-and-epitaxial-strain-on-the-magnetic-structure-of-nimn-fr/
Publication date: Available online 13 February 2019Source: Physics Letters AAuthor(s): Masoud Rahbar Niazi, Sohrab Sanjabi, Yousef JamaliAbstractThe magnetic properties of tetragonal structure of stoichiometric NiMn alloy is investigated using density functional theory within the local spin density approximation. The system studied here, is a free standing film. The effect of thickness and epitaxial strain on the magnetic and structural properties is examined. It is found that while the magnetic moments of Mn surface atoms vary depending on the number of layers being odd (3.60 μB) or even (3.55 μB) the magnitude of the magnetic moment for surface Ni atoms is constant (0.11 μB). By applying epitaxial strain on the slabs, it was observed, for the first time, that the magnetic phase of NiM...Physics Letters AjournalsThu, 14 Feb 2019 13:24:27 +0100669291791Optimum adaptive array stochastic resonance in noisy grayscale image restoration
https://medworm.com/669291790/optimum-adaptive-array-stochastic-resonance-in-noisy-grayscale-image-restoration/
Publication date: Available online 13 February 2019Source: Physics Letters AAuthor(s): Jian Liu, Bing Hu, Youguo WangAbstractConsidering the widespread noise interference in the two-dimensional (2D) image transmission processing, we proposed an optimal adaptive bistable array stochastic resonance (SR)-based grayscale image restoration enhancement method under low peak signal-to-noise ratio (PSNR) environments. In this method, the Hilbert scanning is adopted to reduce the dimension of the original grayscale image. The 2D image signal is converted into a one-dimensional (1D) binary pulse amplitude modulation (BPAM) signal. Meanwhile, we use the adaptive bistable array SR module to enhance the 1D low SNR BPAM signal. In order to obtain the restored image, we transform the enhanced BPAM signal...Physics Letters AjournalsThu, 14 Feb 2019 13:24:27 +0100669291790Structural, optoelectronic and thermoelectric properties of antiperovskite compounds Ae3PbS (Ae = Ca, Sr and Ba): A first principles study
https://medworm.com/668933208/structural-optoelectronic-and-thermoelectric-properties-of-antiperovskite-compounds-ae3pbs-ae-ca/
Publication date: Available online 12 February 2019Source: Physics Letters AAuthor(s): D.M. HoatAbstractIn the last years, alkaline-earth based antiperovskite compounds with small semiconductor band gap have been proven to be promising candidate for optoelectronic and thermoelectric applications. In this work, the structural, electronic, optical and thermoelectric properties of Ae3PbS (Ae = Ca, Sr and Ba) compounds have been predicted using first principles calculations based on the full-potential linearized augmented plane-wave (FP-LAPW) method and semiclassical Boltzmann transport theory. Exchange-correlation effect is treated with the generalized gradient approximation with Perdew–Burke–Ernzerhof scheme (GGA-PBE) and Tran–Blaha modified Becke–Johnson exchange potential. The latt...Physics Letters AjournalsWed, 13 Feb 2019 18:24:24 +0100668933208Interactions between vortex and magnetic rings at high kinetic and magnetic Reynolds numbers
https://medworm.com/668933207/interactions-between-vortex-and-magnetic-rings-at-high-kinetic-and-magnetic-reynolds-numbers/
Publication date: Available online 12 February 2019Source: Physics Letters AAuthor(s): Demosthenes KivotidesAbstractInteractions between magnetic and vortex rings are studied over a wide interval of interaction parameter values ranging from negligible magnetic effects on vorticity structure, to very strong effects. The employed interaction parameter measures the strength of the Lorentz force in units of the inertial force. At small interaction parameters, the vortex ring shapes part of the magnetic ring into a dissipative, curved, magnetic sheet structure. At high interaction parameters, the Lorentz force acts as an agent of proliferation of vortex rings, since it generates two vortex rings adjacent to the original magnetic structure, one of which is pulled (together with the advected magn...Physics Letters AjournalsWed, 13 Feb 2019 18:24:24 +0100668933207Periodic Néel skyrmion transport
https://medworm.com/668933206/periodic-nel-skyrmion-transport/
Publication date: Available online 13 February 2019Source: Physics Letters AAuthor(s): L. Resse, L.G.S. Oliveira, C.I.L. de Araujo, A.R. Pereira, R.L. SilvaAbstractIn this work, we have used the MuMax3 software to simulate devices consisting of a ferromagnetic thin film placed over a heavy metal thin film. The devices are two interconnected partial-disks where a Néel domain wall is formed in the disks junction. In our simulations we investigate devices with disk radius r=50 nm and different distance d between the disks centers (from d=12 nm to d=2R=100 nm). By applying strong sinusoidal external magnetic fields, we find a mechanism able to create, annihilate and even manipulate a skyrmion in each side of the device. This mechanism is discussed in terms of interactions between skyrmion and...Physics Letters AjournalsWed, 13 Feb 2019 18:24:24 +0100668933206Interface induced exchange bias effect in La0.67Sr0.33MnO3/SrIrO3 multilayer
https://medworm.com/668397178/interface-induced-exchange-bias-effect-in-la067sr033mno3sriro3-multilayer/
Publication date: Available online 11 February 2019Source: Physics Letters AAuthor(s): Rachna Chaurasia, K.C. Kharkwal, A.K. PramanikAbstractEpitaxial superlattices of ferromagnetic/paramagnetic La0.67Sr0.33MnO3/SrIrO3 materials have been prepared on SrTiO3 (100) substrate using pulse laser deposition technique. An unexpected onset of interface magnetic interaction has been observed around 40 K. Interestingly, magnetic exchange bias effect has been observed in both field cooled and zero field cooled magnetization loops, however, the shifting of loop is opposite in both measurements. Exchange bias field vanishes as temperature increases to interface magnetic ordering temperature. Moreover, exchange bias field is found to decrease with increasing cooling field. We believe that tuning of magn...Physics Letters AjournalsTue, 12 Feb 2019 14:24:32 +0100668397178Exploring new insights in BAlN from evolutionary algorithms ab initio computations
https://medworm.com/666590517/exploring-new-insights-in-baln-from-evolutionary-algorithms-ab-initio-computations/
Publication date: Available online 7 February 2019Source: Physics Letters AAuthor(s): H. Maiz Hadj Ahmed, H. Benaissa, A. Zaoui, M. FerhatAbstractBN-AlN alloys are potential candidates to achieve wide band gap material for ultraviolet device applications. By combing density functional theory and evolutionary structure predictions, we systematically explore the thermodynamic, mechanical, dynamical and optical properties of BxAl1−xN alloys. Through structure search, three compounds (cubic (BAl3N4, and B3AlN4, space group P-43m), and tetragonal (BAlN2, space group P-42m)) have been predicted. The calculated relative large formation enthalpies suggest that large miscibility gap exists in BAlN alloys. In addition, computed elastic constants and phonon show that these structures are mechanical...Physics Letters AjournalsFri, 08 Feb 2019 16:42:28 +0100666590517Plasmon enhanced light trapping in thin film GaAs solar cells by Al nanoparticle array
https://medworm.com/666045355/plasmon-enhanced-light-trapping-in-thin-film-gaas-solar-cells-by-al-nanoparticle-array/
Publication date: Available online 6 February 2019Source: Physics Letters AAuthor(s): Gurjit Singh, S.S. VermaAbstractLight trapping is a crucial factor to enhance the performance of thin film solar cells. For effective light trapping, we introduced Al nanoparticle array on the top and rear surface of thin film GaAs solar cells. The effect of both array on the optical absorption and current density of solar cells is investigated by using finite difference time domain (FDTD) method. The optimization process of top and rear array in solar cells is done systematically. The results indicate that by plasmonic action of arrays, the optical absorption is significantly enhanced and optimized structure yields a current density of 25.77 mA/cm2. These enhancements are mainly attributed to surface pla...Physics Letters AjournalsThu, 07 Feb 2019 12:42:30 +0100666045355An alternative form of Hooge's relation for 1/f noise in semiconductor materials
https://medworm.com/666045354/an-alternative-form-of-hooges-relation-for-1f-noise-in-semiconductor-materials/
Publication date: Available online 6 February 2019Source: Physics Letters AAuthor(s): Ferdinand GrüneisAbstractSingle quantum dots and other materials exhibit irregular switching between on and off states; these on-off states follow power-law statistics giving rise to 1/f noise. We transfer this phenomenon (also referred to as on-off intermittency) to the generation and recombination (= g–r) process in semiconductor materials. In addition to g–r noise we obtain 1/f noise that can be provided in the form of Hooge's relation. The predicted Hooge coefficient is αH=αXαim whereby αX depends on the parameters of the g–r noise and αim on the parameters of the intermittency. Due to the power-law distribution of the on-times, the coefficient αim shows a smooth dependence on time t. We ...Physics Letters AjournalsThu, 07 Feb 2019 12:42:30 +0100666045354Ballistic thermal transport in black and blue phosphorene nanoribbons and in-plane heterostructures
https://medworm.com/666045352/ballistic-thermal-transport-in-black-and-blue-phosphorene-nanoribbons-and-in-plane-heterostructures/
Publication date: Available online 7 February 2019Source: Physics Letters AAuthor(s): Wei Cao, Huaping Xiao, Tao Ouyang, Ziyu Wang, Rui XiongAbstractThe thermal transport properties of black and blue phosphorene nanoribbons and in-plane heterostructures are systematically investigated by non-equilibrium Green's-function method. Both edge shape and width have a sensitive influence on the thermal conductance of pristine black and blue phosphorene nanoribbons and they all exhibit a clear anisotropic thermal performance. Interestingly, the in-plane heterostructures possess a tunable thermal conductance which depends on the percentage of black phosphorene nanoribbons and the way how they are linked. These findings will provide new applications in nanoelectronic and thermoelectric devices based ...Physics Letters AjournalsThu, 07 Feb 2019 12:42:30 +0100666045352Dynamical analysis of a new multistable chaotic system with hidden attractor: Antimonotonicity, coexisting multiple attractors, and offset boosting
https://medworm.com/665681353/dynamical-analysis-of-a-new-multistable-chaotic-system-with-hidden-attractor-antimonotonicity-coex/
Publication date: Available online 5 February 2019Source: Physics Letters AAuthor(s): Atiyeh Bayani, Karthikeyan Rajagopal, Abdul Jalil M. Khalaf, Sajad Jafari, G.D. Leutcho, J. KengneAbstractAnalyzing chaotic systems with coexisting and hidden attractors has been receiving much attention recently. In this article, we analyze a four dimensional chaotic system which has a plane as the equilibrium points. Also this system is of the group of systems that have coexisting attractors. First, the system is introduced and then stability analysis, bifurcation diagram and Largest Lyapunov exponent of this system are presented as methods to analyze the multistability of the system. These methods reveal that in some ranges of the parameter, this chaotic system has three different types of coexisting a...Physics Letters AjournalsWed, 06 Feb 2019 18:06:24 +0100665681353Modes conversion due to plasmons induced transparency
https://medworm.com/665681352/modes-conversion-due-to-plasmons-induced-transparency/
Publication date: Available online 5 February 2019Source: Physics Letters AAuthor(s): Wanxia Huang, Chaogang Li, Maosheng Wang, Yong Zhou, Cunyuan Zhu, Kuanguo Li, Xinyan Yang, Fabao ZhangAbstractWe investigate simulated and theoretically the optical properties of the metamaterial, composed of two bigger split ring resonators and one smaller split ring resonator in unit cell. We observe the magic phenomena that one mode B is inhibited from strong to weak then disappears while another mode A appears and becomes stronger and stronger as asymmetric degree increases. The results show the mode A originates from the destructive interference between the dipole mode and the quadrapole mode, and its strength is proportional to the cross coupling coefficient of near-field. The disappearance of the m...Physics Letters AjournalsWed, 06 Feb 2019 18:06:24 +0100665681352Levitation of a Rapidly Oscillating Magnetic Dipole Above a Metallic Sheet
https://medworm.com/665681351/levitation-of-a-rapidly-oscillating-magnetic-dipole-above-a-metallic-sheet/
Publication date: Available online 5 February 2019Source: Physics Letters AAuthor(s): B. ShayakAbstractWe show that such a magnetic dipole suspended at a height h above a conducting sheet experiences a lift force proportional to 1/h2. This represents an order of magnitude improvement over the 1/h4 lift obtained in the quasistatic limit. (Source: Physics Letters A)Physics Letters AjournalsWed, 06 Feb 2019 18:06:24 +0100665681351Effective equation for quasi-one dimensional tube-shaped Bose–Einstein condensates
https://medworm.com/665681349/effective-equation-for-quasi-one-dimensional-tube-shaped-boseeinstein-condensates/
Publication date: Available online 5 February 2019Source: Physics Letters AAuthor(s): Mateus C.P. dos Santos, Wesley B. CardosoAbstractIn this letter we derive an effective 1D equation that describes the axial dynamics of a tube-shaped Bose–Einstein condensate. The dimensional reduction is achieved by using a variational approach starting from the 3D Gross–Pitaevskii equation (GPE) in presence of a nonharmonic external potential in the transverse direction and generic in the axial one. The resulting equation is a time-dependent 1D nonpolynomial Schrödinger equation (NPSE). In view to check the accuracy of our 1D-NPSE, we numerically investigated the ground state properties of such a system that are in perfect agreement with the results produced by the 3D-GPE. We also compare the resul...Physics Letters AjournalsWed, 06 Feb 2019 18:06:24 +0100665681349Study of a dynamical system with a strange attractor and invariant tori
https://medworm.com/665681348/study-of-a-dynamical-system-with-a-strange-attractor-and-invariant-tori/
Publication date: Available online 5 February 2019Source: Physics Letters AAuthor(s): Antonio Algaba, Manuel Merino, Bowei Qin, Alejandro J. Rodríguez-LuisAbstractA simple three-dimensional time-reversible system of ODEs with quadratic nonlinearities is considered in a recent paper Sprott (2014) [37]. The author finds in this system, that has no equilibria, the coexistence of a strange attractor and invariant tori. The goal of this letter is to justify theoretically the existence of infinite invariant tori and chaotic attractors. For this purpose we embed the original system in a one-parameter family of reversible systems. This allows to demonstrate the presence of a Hopf-zero bifurcation that implies the birth of an elliptic periodic orbit. Thus, the application of the KAM theory guarant...Physics Letters AjournalsWed, 06 Feb 2019 18:06:24 +0100665681348Modeling complex networks with accelerating growth and aging effect
https://medworm.com/665681347/modeling-complex-networks-with-accelerating-growth-and-aging-effect/
Publication date: Available online 5 February 2019Source: Physics Letters AAuthor(s): Jin Liu, Jian Li, Chen Yadang, Xianyi Chen, Zhili Zhou, Zejun Yang, Cheng-Jun ZhangAbstractNumerous empirical studies have revealed that a large number of real networks exhibit the property of accelerating growth, i.e. network size (nodes) increases superlinearly with time. Examples include the size of social networks, the output of scientists, the population of cities, and so on. In the literature, these real systems are widely represented by complex networks for analysis, and many network models have been proposed to explain the observed properties in these systems such as power-law degree distribution. However, most of these models (e.g. the well-known BA model) are based on linear growth of these syst...Physics Letters AjournalsWed, 06 Feb 2019 18:06:24 +0100665681347Hole-Polarons and Bipolarons in the Holstein t − J model: Relevance of Inter-site Hole-phonon Interaction
https://medworm.com/665681346/hole-polarons-and-bipolarons-in-the-holstein-tj-model-relevance-of-inter-site-hole-phonon-/
Publication date: Available online 6 February 2019Source: Physics Letters AAuthor(s): Krishanu Roy, Subhadip Nath, Kumar GhoshAbstractThe interaction of the doped holes with lattice vibrations in an antiferromagnetic (AF) background is studied using the t−J-Holstein model on an 8-site cluster with 2-holes by an exact method. The phonon mediated interactions between the holes at nearest-neighbor (NN) sites are considered. We have calculated the effective kinetic energy, hole-phonon and hole-hole correlations, two hole binding energy to study the nature and stability of various quasiparticles. At negligible to very weak hole-phonon (h−ph) couplings, the holes get dressed by the AF background forming spin-polarons. At weak to intermediate h−ph couplings, the holes are dressed by the pho...Physics Letters AjournalsWed, 06 Feb 2019 18:06:24 +0100665681346Ground-state phase diagram of the 1-D Holstein–Hubbard model
https://medworm.com/665318887/ground-state-phase-diagram-of-the-1-d-holsteinhubbard-model/
Publication date: Available online 5 February 2019Source: Physics Letters AAuthor(s): M. Zahid Malik, Soma Mukhopadhyay, Ashok ChatterjeeAbstractThe Holstein–Hubbard model is investigated in one-dimension at half filling employing a series of unitary transformations taking into account the coherence and correlation of phonons. To treat the phonon subsystem more accurately a new squeezing transformation is introduced to incorporate the electron-density-dependent onsite phonon correlations to lower the energy further. The effective electronic Hamiltonian is next obtained by averaging the transformed Hamiltonian with respect to the zero-phonon state and the resulting effective electronic Hamiltonian is solved exactly using the method of Bethe ansatz. Finally the ground state is obtained by ...Physics Letters AjournalsTue, 05 Feb 2019 23:12:31 +0100665318887A steady state quantum classifier
https://medworm.com/663878436/a-steady-state-quantum-classifier/
We report that under some specific conditions a single qubit model weakly interacting with information environments can be referred to as a quantum classifier. We exploit the additivity and the divisibility properties of the completely positive (CP) quantum dynamical maps in order to obtain an open quantum classifier. The steady state response of the system with respect to the input parameters was numerically investigated and it's found that the response of the open quantum dynamics at steady state acts non-linearly with respect to the input data parameters. We also demonstrate the linear separation of the quantum data instances that reflects the success of the functionality of the proposed model both for ideal and experimental conditions. Superconducting circuits were pointed out as the p...Physics Letters AjournalsSat, 02 Feb 2019 19:24:25 +0100663878436Designing a broad locally-resonant bandgap in a phononic crystals
https://medworm.com/663878435/designing-a-broad-locally-resonant-bandgap-in-a-phononic-crystals/
This study opens new possibilities to broaden locally-resonant bandgaps of phononic crystals for low frequencies. The results can potentially be used to reduce vibration and noise in many applications. (Source: Physics Letters A)Physics Letters AjournalsSat, 02 Feb 2019 19:24:25 +0100663878435The 2D Kramers–Dirac oscillator
https://medworm.com/663878434/the-2d-kramersdirac-oscillator/
Publication date: Available online 1 February 2019Source: Physics Letters AAuthor(s): T. Iwai, B. ZhilinskiiAbstractThe Dirac oscillator was initially introduced as a Dirac operator which is linear in momentum and coordinate variables. In contrast to the usual 2D Dirac oscillator, the 2D Kramers–Dirac oscillator admits the time-reversal symmetry, which is a reason for the present nomenclature. It is shown that there exists a family of eigenstates associated with an eigenvalue linear in the control parameter, and the eigenvalue in question goes down from positive values to negative values as the parameter varies in the positive direction. The other eigenvalues are broken up into two bands, positive and negative. The 2D Dirac and the 2D Kramers–Dirac oscillators are compared in their phy...Physics Letters AjournalsSat, 02 Feb 2019 19:24:25 +0100663878434Electronic and optical properties of van der Waals vertical heterostructures based on two-dimensional transition metal dichalcogenides: First-principles calculations
https://medworm.com/663878433/electronic-and-optical-properties-of-van-der-waals-vertical-heterostructures-based-on-two-dimensiona/
Publication date: Available online 1 February 2019Source: Physics Letters AAuthor(s): Kai Ren, Minglei Sun, Yi Luo, Sake Wang, Yujing Xu, Jin Yu, Wencheng TangAbstractFour vertical heterostructures based on two-dimensional transition-metal dichalcogenides (TMDs) – MoS2/GeC, MoSe2/GeC, WS2/GeC, and WSe2/GeC, were studied by density functional theory calculations to investigate their structure, electronic characteristics, principle of photogenerated electron–hole separation, and optical-absorption capability. The optimized heterostructures were formed by van der Waals (vdW) forces and without covalent bonding. Their most stable geometric configurations and band structures display type-II band alignment, which allows them to spontaneously separate photogenerated electrons and holes. The c...Physics Letters AjournalsSat, 02 Feb 2019 19:24:25 +0100663878433Pressure-dependent photoluminescence of CdSe/ZnS quantum dots: critical point of different pressure regimes
https://medworm.com/663878432/pressure-dependent-photoluminescence-of-cdsezns-quantum-dots-critical-point-of-different-pressure-/
Publication date: Available online 1 February 2019Source: Physics Letters AAuthor(s): Bo Li, Weilong Liu, Xiaojun Zhu, Shan Lin, Yanqiang Yang, Qingxin Yang, Peng JinAbstractHigh pressure condition can alter and control the electronic structure of semiconductor quantum dots, and therefore provides novel insight for designing optoelectronic devices. Here we report the pressure-dependent photoluminescence (PL) of CdSe/ZnS core/shell quantum dots (QD) in different pressure regimes. The center of the PL spectrum has blue-shift when hydrostatic pressure increases, due to the increasing bulk modulus. However, the shifting rate becomes lower in the higher pressure regime, i.e. above the critical pressure point, mainly due to the interaction between QDs. Accordingly, the lifetimes of PL drop in th...Physics Letters AjournalsSat, 02 Feb 2019 19:24:25 +0100663878432The fate of self-aligned rolls in gravity modulated magnetoconvection
https://medworm.com/663338334/the-fate-of-self-aligned-rolls-in-gravity-modulated-magnetoconvection/
Publication date: Available online 31 January 2019Source: Physics Letters AAuthor(s): Arnab BasakAbstractWe explore the modifications brought about by gravity modulation in self-aligned two-dimensional (2D) stationary rolls and higher-order convective instabilities with horizontal magnetic field. The Chandrasekhar number plays no role in determining critical values of the forcing parameters for convection to begin. The onset is in the form of 2D rolls with periodically varying intensity. The external magnetic field is solely responsible for aligning the rolls while the induced magnetic field comes into play after three-dimensional convection sets in. Gravity modulation destabilizes the system and results in chaotic flow much earlier above onset. (Source: Physics Letters A)Physics Letters AjournalsFri, 01 Feb 2019 15:24:33 +0100663338334High-performance refractive index sensor based on guided-mode resonance in all-dielectric nano-silt array
https://medworm.com/662795884/high-performance-refractive-index-sensor-based-on-guided-mode-resonance-in-all-dielectric-nano-silt-/
Publication date: Available online 30 January 2019Source: Physics Letters AAuthor(s): Guilian Lan, Song Zhang, Hong Zhang, Yuhang Zhu, Longyu Qing, Daimin Li, Jinpeng Nong, Wei Wang, Li Chen, Wei WeiAbstractWe propose a high-quality refractive index sensing by utilizing the characteristic guided-mode resonance (GMR) excited in a simple one-dimensional all-dielectric nano-slit array. We demonstrate a figure of merit up to 12000, which is higher than that achieved in most plasmonic refractive index sensors. We show that high-quality sensing performance can be sustained over a broadband range in near infrared region with relatively large variations in both grating depth and angle of incidence. Such a GMR-based all-dielectric sensing device with the ease of fabrication is expected to hold grea...Physics Letters AjournalsThu, 31 Jan 2019 11:09:35 +0100662795884Editors
https://medworm.com/662795865/editors/
Publication date: 11 February 2019Source: Physics Letters A, Volume 383, Issue 8Author(s): (Source: Physics Letters A)Physics Letters AjournalsThu, 31 Jan 2019 11:09:35 +0100662795865Interaction of Love waves with coupled cavity modes in a 2D holey phononic crystal
https://medworm.com/662439533/interaction-of-love-waves-with-coupled-cavity-modes-in-a-2d-holey-phononic-crystal/
Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): Yuxin Liu, Abdelkrim Talbi, Bahram Djafari-Rouhani, El Houssaine El Boudouti, Lucie Drbohlavová, Vincent Mortet, Olivier Bou Matar, Philippe PernodAbstractThe interaction of Love waves with square array of pillars deposited on a cavity defined in a 2D holey phononic crystal is numerically investigated using Finite Element Method. First, the existence of SH surface modes is demonstrated separately for phononic crystals that consist of square arrayed holes, or rectangular arrayed Ni pillars, respectively in, or on, a SiO2 film deposited on a ST-cut quartz substrate. The coupling between SH modes and torsional mode in pillars induces a transmission dip that occurs at a frequency located in the range of the ...Physics Letters AjournalsWed, 30 Jan 2019 16:24:36 +0100662439533The synchronization method for fractional-order hyperchaotic systems
https://medworm.com/662439532/the-synchronization-method-for-fractional-order-hyperchaotic-systems/
Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): Dali Feng, Hongli An, Haixing Zhu, Yunfeng ZhaoAbstractIn this paper, a function cascade synchronization method for fractional-order hyperchaotic systems is introduced to achieve the synchronization of two identical fractional-order hyperchaotic systems. It is shown that the method is not only theoretically rigorous, practically feasible, but also a more general one, which contains the complete synchronization, modified projective synchronization and anti-phase synchronization. In order to valid the effectiveness of the proposed method, we give two illustrative examples. Suitable controllers are designed and the function cascade synchronization for fractional-order hyperchaotic systems is achieved. Numeri...Physics Letters AjournalsWed, 30 Jan 2019 16:24:36 +0100662439532Quantum topological transitions and spinons in metallic ferro- and antiferromagnets
https://medworm.com/662439531/quantum-topological-transitions-and-spinons-in-metallic-ferro-and-antiferromagnets/
Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): V.Yu. IrkhinAbstractAn effective Hamiltonian describing fluctuation effects in the magnetic phases of the Hubbard model in terms of spinon excitations is derived. A comparison of spin-rotational Kotliar–Ruckenstein slave boson and Ribeiro–Wen dopon representations is performed. The quantum transition into the half-metallic ferromagnetic state with vanishing of spin-down Fermi surface is treated as the topological Lifshitz transition in the quasimomentum space. The itinerant-localized magnetism transitions and Mott transition in antiferromagnetic state are considered in the topological context. Related metal-insulator transitions in Heusler alloys are discussed. (Source: Physics Letters A)Physics Letters AjournalsWed, 30 Jan 2019 16:24:36 +0100662439531Fluxon interaction with the finite-size dipole impurity
https://medworm.com/662439530/fluxon-interaction-with-the-finite-size-dipole-impurity/
Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): Ivan O. Starodub, Yaroslav ZolotaryukAbstractInteraction of the fluxon with the finite size dipole impurity in the long Josephson junction is investigated. The impurity has polarity and will be referred to as a dipole impurity because it also has a direction and, consequently, changes its sign under the space inversion transform x→−x. Such a model is used to describe the inductively coupled to the Josephson transmission line qubit and the misaligned Abrikosov vortex that penetrates into the long Josephson junction. We derive the approximate equations of motion for the fluxon centre of mass and its velocity. With the help of these equations we demonstrate that pinning and scattering of the fluxon on th...Physics Letters AjournalsWed, 30 Jan 2019 16:24:36 +0100662439530Intrinsic edge warping of graphene nanoribbon boost molecular directional motion: Toward the novel nanodevices
https://medworm.com/662439529/intrinsic-edge-warping-of-graphene-nanoribbon-boost-molecular-directional-motion-toward-the-novel-n/
Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): Yafei Wang, Changguo Wang, Huifeng TanAbstractIn this letter, nanodirectional motion due to intrinsic warping edge of graphene nanoribbon is demonstrated using theoretical analysis and molecular dynamics (MD) simulation. Simulation model is established and the underlying physical insights of intrinsic nanodirectional motion are investigated. It is found that nanodirectional motion of carbon fullerene is gradient-dependent. Directional motion with +z-warping graphene edge is energetically favorable over the −z-warping configuration. As a result, a novel nanodirectional motion actuator inspired by intrinsic edge warping with Gaussian curvature can be designed. The obtained results in current research are ...Physics Letters AjournalsWed, 30 Jan 2019 16:24:36 +0100662439529Finite temperature aspect ratio in ultra-cold Bose gas for large N
https://medworm.com/661904943/finite-temperature-aspect-ratio-in-ultra-cold-bose-gas-for-large-n/
We present a detailed study of the temperature dependence of the condensate fraction, collective excitation and aspect ratio profiles of a Bose-condensed gas in a harmonic trap for large numbers of condensate atoms up to 85000. These quantities are calculated self-consistently using the generalized Hartree–Fock–Bogoliubov (GHFB) equations. We determine the evolution of the aspect ratio at zero and finite temperature via the condensed fraction. We compare our results with experimental data and we find a good agreement. (Source: Physics Letters A)Physics Letters AjournalsTue, 29 Jan 2019 12:24:27 +0100661904943CN-Smorodinsky–Winternitz system in a constant magnetic field
https://medworm.com/661904942/cn-smorodinskywinternitz-system-in-a-constant-magnetic-field/
Publication date: Available online 28 January 2019Source: Physics Letters AAuthor(s): Hovhannes ShmavonyanAbstractWe propose the superintegrable generalization of Smorodinsky–Winternitz system on the N-dimensional complex Euclidian space which is specified by the presence of constant magnetic field. We find out that in addition to 2N Liouville integrals the system has additional functionally independent constants of motion, and compute their symmetry algebra. We perform the Kustaanheimo–Stiefel transformation of C2-Smorodinsky–Winternitz system to the (three-dimensional) generalized MICZ-Kepler problem and find the symmetry algebra of the latter one. We observe that constant magnetic field appearing in the initial system has no qualitative impact on the resulting system. (Source: Phy...Physics Letters AjournalsTue, 29 Jan 2019 12:24:27 +0100661904942Effects of built-in electric field on donor binding energy in InGaN/ZnSnN2 quantum well structures
https://medworm.com/661904941/effects-of-built-in-electric-field-on-donor-binding-energy-in-inganznsnn2-quantum-well-structures/
Publication date: Available online 28 January 2019Source: Physics Letters AAuthor(s): Hasan YıldırımAbstractInxGa1−xN/ZnSnN2 quantum well structures are studied in terms of a binding energy of a donor atom. 1s and 2p± impurity states are considered. The Schrödinger's and Poisson's equations are solved self-consistently. A hydrogenic type wave function to represent each impurity state is assumed. The calculations include band-bending in the potential energy profile introduced by the built-in electric field existing along the structures. The binding energy and the energy of the transition between the impurity states are represented as a function of the quantum well width, the donor position, and the indium concentration. An external magnetic field up to 10 T is included into the calcu...Physics Letters AjournalsTue, 29 Jan 2019 12:24:27 +0100661904941Chiral anomaly in Weyl systems: No violation of classical conservation laws
https://medworm.com/661904940/chiral-anomaly-in-weyl-systems-no-violation-of-classical-conservation-laws/
Publication date: Available online 28 January 2019Source: Physics Letters AAuthor(s): K. MorawetzAbstractThe anomalous term ∼EB in the balance of the chiral density can be rewritten as quantum current in the classical balance of density. Therefore it does not violate conservation laws as sometimes claimed to be caused by quantum fluctuations. (Source: Physics Letters A)Physics Letters AjournalsTue, 29 Jan 2019 12:24:27 +0100661904940Justification of the discrete nonlinear Schrödinger equation from a parametrically driven damped nonlinear Klein–Gordon equation and numerical comparisons
https://medworm.com/661904937/justification-of-the-discrete-nonlinear-schrdinger-equation-from-a-parametrically-driven-damped-no/
Publication date: Available online 28 January 2019Source: Physics Letters AAuthor(s): Y. Muda, F.T. Akbar, R. Kusdiantara, B.E. Gunara, H. SusantoAbstractWe consider a damped, parametrically driven discrete nonlinear Klein–Gordon equation, that models coupled pendula and micromechanical arrays, among others. To study the equation, one usually uses a small-amplitude wave ansatz, that reduces the equation into a discrete nonlinear Schrödinger equation with damping and parametric drive. Here, we justify the approximation by looking for the error bound with the method of energy estimates. Furthermore, we prove the local and global existence of solutions to the discrete nonlinear Schrödinger equation. To illustrate the main results, we consider numerical simulations showing the dynamics of ...Physics Letters AjournalsTue, 29 Jan 2019 12:24:27 +0100661904937Energy gaps and half-metallicity in β-graphyne nanoribbons
https://medworm.com/661904925/energy-gaps-and-half-metallicity-in-graphyne-nanoribbons/
Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): Yan-Qing Liu, Lei Xu, Jun ZhangAbstractWe investigate the energy gaps and half-metallicity of the zigzag-edged β-graphyne nanoribbons via a tight-binding approach. In the presence of on-site Coulomb repulsion and proper transverse electric field strengths, the nanoribbons are forced into a half-metallic state by the electric field. A phase transition from half-metal to insulator is realized by changing the electric field or Coulomb potential. Both the electric field and Coulomb repulsion can open direct band gaps, resulting in a metal-insulator phase transition. The band gaps oscillate with the electric field, contrary to linear change with the Coulomb potential. (Source: Physics Letters A)Physics Letters AjournalsTue, 29 Jan 2019 12:24:27 +0100661904925On the weakly-bound (1,1)-states in the three-body ddμ and dtμ muonic ions
https://medworm.com/661904924/on-the-weakly-bound-11-states-in-the-three-body-dd-and-dt-muonic-ions/
Publication date: Available online 29 January 2019Source: Physics Letters AAuthor(s): Alexei M. FrolovAbstractThe both total and binding energies of the (1,1)-states in the weakly-bound three-body muonic ddμ and dtμ ions are determined to high numerical accuracy. The binding energy of the (1,1)-state in the muonic dtμ ion is evaluated as ε(dtμ)=−0.66033003831(30)eV, while for the same state in the muonic ddμ ion we have found that ε(ddμ)=−1.9749806166970(30)eV. These energies are the most accurate numerical values obtained for these systems and they are sufficient for all current and future experimental needs. (Source: Physics Letters A)Physics Letters AjournalsTue, 29 Jan 2019 12:24:27 +0100661904924Lump-soliton solutions to the Fokas system
https://medworm.com/660658360/lump-soliton-solutions-to-the-fokas-system/
Publication date: Available online 25 January 2019Source: Physics Letters AAuthor(s): Jiguang Rao, Dumitru Mihalache, Yi Cheng, Jingsong HeAbstractIn this letter, we obtain families of semi-rational solutions termed lump-soliton solutions to the Fokas system by using the Hirota's bilinear method combined with the Kadomtsev-Petviashvili (KP) hierarchy reduction method. These exact semi-rational solutions illustrate the collision of lumps and dark-line solitons. Two different types of evolution scenarios occur: (a) fusion of lumps and dark-line solitons into dark-line solitons, and (b) fission of dark-line solitons into lumps and dark-line solitons. In these distinct evolution processes, the lumps would get either created or annihilated by the dark-line solitons. (Source: Physics Letters A)Physics Letters AjournalsSat, 26 Jan 2019 18:30:26 +0100660658360Delay of terminal current in systems with abruptly changed Hamiltonian
https://medworm.com/660123979/delay-of-terminal-current-in-systems-with-abruptly-changed-hamiltonian/
Publication date: Available online 24 January 2019Source: Physics Letters AAuthor(s): Mou Yang, Xian-Jin Ran, Bo Su, Rui-Qiang WangAbstractThe current response for the parameter change of a mesoscopic system is a practical issue for future's circuit design. Nowadays most considered cases are varied types of bias modulation, while the effect of change of conductor Hamiltonian is seldom addressed. In this paper, we investigate the response of ballistic transport induced by a sudden change of the conductor Hamiltonian. We formulize the terminal current in language of non-equilibrium Green's function. Our method is applied to one-dimensional tight-binding chains and we find that the terminal current has a delay to the Hamiltonian change. The amount of delay is not determined by the velocity of...Physics Letters AjournalsFri, 25 Jan 2019 14:18:27 +0100660123979Plasmon modes in MLG-2DEG heterostructures: Temperature effects
https://medworm.com/660123978/plasmon-modes-in-mlg-2deg-heterostructures-temperature-effects/
Publication date: Available online 24 January 2019Source: Physics Letters AAuthor(s): Nguyen Van Men, Nguyen Quoc Khanh, Dong Thi Kim PhuongAbstractWe calculate the plasmon frequency and damping rate in a double-layer system made of monolayer graphene and GaAs quantum well at finite temperature using the random-phase-approximation dielectric function and taking into account the inhomogeneity of the dielectric background of the system. We show that the temperature, interlayer correlation parameters and dielectric background inhomogeneity affect significantly the plasmon frequencies and damping rates of the system. At low temperatures, acoustic (optical) plasmon frequency increases (decreases) with the increase of temperature. We also find that damping rates of both plasmon modes increase re...Physics Letters AjournalsFri, 25 Jan 2019 14:18:27 +0100660123978Investigating the nonequilibrium aspects of long-range Potts model: Refinement of critical temperatures and raw exponents
https://medworm.com/660123977/investigating-the-nonequilibrium-aspects-of-long-range-potts-model-refinement-of-critical-temperatu/
Publication date: Available online 25 January 2019Source: Physics Letters AAuthor(s): Roberto da Silva, J.R. Drugowich de Felicio, Henrique A. FernandesAbstractIn this work, we analyse the q−state Potts model with long-range interactions through nonequilibrium scaling relations commonly used when studying short-range systems. We determine the critical temperature via an optimization method for short-time Monte Carlo simulations. The study takes into consideration two different boundary conditions and three different values of range parameters of the couplings. We also present estimates of some critical exponents, named as raw exponents for systems with long-range interactions, which confirm the non-universal character of the model. Finally, we provide some preliminary results addressing ...Physics Letters AjournalsFri, 25 Jan 2019 14:18:27 +0100660123977Noise-induced multilevel Landau–Zener transitions: Density matrix investigation
https://medworm.com/659224103/noise-induced-multilevel-landauzener-transitions-density-matrix-investigation/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): I.F. Nyisomeh, M.E. Ateuafack, L.C. FaiAbstractThe generalised multilevel Landau–Zener problem is solved by applying the density matrix technique within the framework of nonstationary perturbation theory. The exact survival probability is achieved as a proof of the Brundobler–Elzer hypothesis (Brundobler and Elzer (1993) [38]). The effect of classical Gaussian noise is investigated by averaging the solution over the noise realisation. A generalised formula for slow noise-induced transition probability is obtained and found to agree exactly with all known results. Exact results are reported for the Demkov–Osherov model in the slow and fast noise limits. Thermal transition probabilities are obtained v...Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224103A quantummechanical derivation of the eigenvalues of the quadratic Casimir operator of the algebra SU(n) in Young tableau representation
https://medworm.com/659224094/a-quantummechanical-derivation-of-the-eigenvalues-of-the-quadratic-casimir-operator-of-the-algebra-s/
Publication date: Available online 22 January 2019Source: Physics Letters AAuthor(s): Éva SzőkeAbstractThe paper concerns the eigenvalues and eigenfunctions of the quadratic Casimir operator of the algebra SU(n) in the Young tableau representation. Our starting point is a concrete physical problem in second quantized formalism. We use quantummechanical and group theoretical vehicles to determine the aimed quantities. The tableaux are organized according to their eigenvalue. We also investigate the modification rules. (Source: Physics Letters A)Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224094Introduction in the band theory of molten salts
https://medworm.com/659224093/introduction-in-the-band-theory-of-molten-salts/
Publication date: Available online 22 January 2019Source: Physics Letters AAuthor(s): Alexander L. ShimkevichAbstractThe electrochemical properties of molten salts are considered in the frame of band theory for ideal crystalline dielectrics. It turned out that metal impurities at low concentration in them generate the local electron levels in the wide band gap (>4 eV) of molten salt divided by 50 meV and more. They are occupied by electrons when Fermi level is approached to them from below. Then, the minor metal impurities fall out the molten salt when the electron occupation of their energy levels in the band gap achieves their solubility (<0.1 ppm) in the molten salt. At the same time, the given RedOx-potential of molten salt can be maintained without chemical additives but forced sh...Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224093Comparison of diluted antiferromagnetic Ising models on frustrated lattices in a magnetic field
https://medworm.com/659224091/comparison-of-diluted-antiferromagnetic-ising-models-on-frustrated-lattices-in-a-magnetic-field/
Publication date: Available online 22 January 2019Source: Physics Letters AAuthor(s): Konstantin Soldatov, Alexey Peretyatko, Petr Andriushchenko, Konstantin Nefedev, Yutaka OkabeAbstractWe study diluted antiferromagnetic Ising models on triangular and kagome lattices in a magnetic field, using the replica-exchange Monte Carlo method. We observe seven and five plateaus in the magnetization curve of the diluted antiferromagnetic Ising model on the triangular and kagome lattices, respectively, when a magnetic field is applied. These observations contrast with the two plateaus observed in the pure model. The origin of multiple plateaus is investigated by considering the spin configuration of triangles in the diluted models. We compare these results with those of a diluted antiferromagnetic Is...Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224091Cooperative activation effect on H2O adsorption in MnO–Co catalyzed steam methane reforming
https://medworm.com/659224090/cooperative-activation-effect-on-h2o-adsorption-in-mnoco-catalyzed-steam-methane-reforming/
Publication date: Available online 22 January 2019Source: Physics Letters AAuthor(s): Zhaoming Fu, Meng Liu, Qian Sun, Dongwei Ma, Zongxian YangAbstractSteam methane reforming is a very important chemical process in hydrogen production and solid oxide fuel cells (SOFCs). Cobalt (Co) is an important catalyst for dry and steam methane reforming. However, previous studies have confirmed that metal Co surfaces only have weak adsorption activity for H2O, which is evidently unfavorable for steam reforming. In this work we used first-principles simulations to study the activity of MnO–Co catalysts for the adsorption of H2O, Compared with the Co (111) surface and pristine Co clusters, the MnO–Co catalytic layer has a stronger adsorption capability for H2O because of the introduction of the MnO...Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224090PageRank centrality for temporal networks
https://medworm.com/659224089/pagerank-centrality-for-temporal-networks/
Publication date: Available online 23 January 2019Source: Physics Letters AAuthor(s): Laishui Lv, Kun Zhang, Ting Zhang, Dalal Bardou, Jiahui Zhang, Ying CaiAbstractIn this paper, we propose a new centrality measure for ranking the nodes and time layers of temporal networks simultaneously, referred to as the f-PageRank centrality. The f-PageRank values of nodes and time layers in temporal networks are obtained by solving the eigenvector of a multi-homogeneous map. The existence and uniqueness of the proposed centrality measure are also guaranteed by existing results, under some reasonable conditions. The numerical experiments on a synthetic temporal network and two real-world temporal networks(i.e., Email-Eu-core and CollegeMsg temporal networks) show that the proposed centrality outperfor...Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224089MMSE detection method in uplink massive MIMO systems based on quantum computing
https://medworm.com/659224088/mmse-detection-method-in-uplink-massive-mimo-systems-based-on-quantum-computing/
Publication date: Available online 23 January 2019Source: Physics Letters AAuthor(s): XiaoJun Wang, Jie Zhao, FanXu Meng, XuTao Yu, ZaiChen ZhangAbstractThe minimum mean square error (MMSE) detection method involved matrix inversion operation with excessive computational burden. In this paper, we develop an improved quantum linear system algorithm to solve matrix inversion problem of the MMSE detection method in uplink massive multiple-input and multiple-output (MIMO) systems. In order to apply reasonably the robust computational power of quantum computing, we optimize the preparation of the input state and the extraction of the solution from the final entangled quantum state. We prove that this algorithm can reduce computational complexity to O(NlogN). (Source: Physics Letters A)Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224088Editors
https://medworm.com/659224072/editors/
Publication date: 4 February 2019Source: Physics Letters A, Volume 383, Issue 7Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 23 Jan 2019 14:42:31 +0100659224072Quantum information capsule and information delocalization by entanglement in multiple-qubit systems
https://medworm.com/658864277/quantum-information-capsule-and-information-delocalization-by-entanglement-in-multiple-qubit-systems/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): Koji Yamaguchi, Naoki Watamura, Masahiro HottaAbstractWhere do entangled multiple-qubit systems store information? For information injected into a qubit, this question is nontrivial and interesting since the entanglement delocalizes the information. So far, a common picture is that of a qubit and its purification partner sharing the information quantum mechanically. Here, we introduce a new picture of a single qubit in the correlation space, referred to as quantum information capsule (QIC), confining the information perfectly. This picture is applicable for the entangled multiple-qubit system in an arbitrary state. Unlike the partner picture, in the QIC picture, by swapping the single-body state, leaving ...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864277The intrinsical character of the electronic correlation in an electron gas
https://medworm.com/658864276/the-intrinsical-character-of-the-electronic-correlation-in-an-electron-gas/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): Yu-Liang LiuAbstractBy introducing the phase transformation of electron operators, we map the equation of motion of an one-particle Green's function into that of a non-interacting one-particle Green's function where the electrons are moving in a time-depending scalar potential and pure gauge fields for a D-dimensional electron gas, and we demonstrate that the electronic correlation strength strongly depends upon the excitation energy spectrum and collective excitation modes of electrons. It naturally explains that the electronic correlation strength is strong in the one dimension, while it is weak in the three dimensions. (Source: Physics Letters A)Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864276Inherent spectral distortions in pump-probe Brillouin scattering spectroscopy
https://medworm.com/658864275/inherent-spectral-distortions-in-pump-probe-brillouin-scattering-spectroscopy/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): V.I. KovalevAbstractIt is shown that the pump-probe technique in Brillouin scattering spectroscopy is accompanied by two specific distortions to a registered spectrum. The first appears due to an acoustic wave that unavoidably accompanies in a continuous medium the density wave driven by the pump and probe signals. The registered spectrum then splits to two spectral components, one corresponding to the propagation velocity of the driven density wave, and the other to the acoustic velocity. The other distortion is asymmetry of the spectrum which is shown to occur when the velocity of the driven density wave is greater than the acoustic velocity in the medium. (Source: Physics Letters A)Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864275Spin switch effect in multiply connected superconductor-ferromagnet hybrid geometry
https://medworm.com/658864273/spin-switch-effect-in-multiply-connected-superconductor-ferromagnet-hybrid-geometry/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): B. KrunavakarnAbstractWe consider a superconducting spin valve in multiply connected superconductor-ferromagnet hybrid geometry such as a superconducting ring enclosed a ferromagnetic metal, in the framework of linearized Usadel equations. We simplify our model by considering the presence of the exchange field in the superconducting ring which allows us to manipulate magnetization orientations in parallel or antiparallel configurations by switching the weaker exchange field. In such geometry the superconducting ground state is activated to higher orbital states characterized by the nonvanishing vorticity parameters L which will be the energetically favorable superconducting state in some ranges of the pro...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864273Scanning tunneling microscopy studies in the heavy fermion system with even and odd hybridization
https://medworm.com/658864272/scanning-tunneling-microscopy-studies-in-the-heavy-fermion-system-with-even-and-odd-hybridization/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): Fu-Bin YangAbstractThe effect of even and odd hybridization for scanning-tunneling microscopy process in the heavy fermion system is studied by the nonequilibrium Green function method. It is found that an even hybridization leads to symmetric density of states (DOS), while an odd hybridization leads to the vanishing of the DOS of the nondiagonal term. Besides, the differential conductance under the even hybridization is the natural consequence of the existence of van Hove singularities. In the odd hybridization situation, the differential conductance reflects the interference between normal tunneling and cotunneling is absent in the simplest tunneling models. The results obtained provide valuable theoret...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864272Effect of energy dependent cross-section on flow velocity measurements with charge exchange spectroscopy in magnetized plasma
https://medworm.com/658864271/effect-of-energy-dependent-cross-section-on-flow-velocity-measurements-with-charge-exchange-spectros/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): J. Chen, K. Ida, M. Yoshinuma, I. Murakami, T. Kobayashi, M.Y. Ye, B. LyuAbstractCharge exchange spectroscopy (CXS) is widely used to measure plasma flow velocity. Accurate measurement is heavily affected by energy dependent cross section between neutral atoms and impurity ions. One symmetric layout of poloidal CXS is applied on Large Helical Device. Correction velocity due to the cross section is exacted from total velocity when actual plasma flow velocity is acquired with the benefit of this layout. A linear relationship between correction velocity and ion temperature is observed. Abundant discharges with wide plasma conditions are investigated and the ratio of correction velocity to ion temperature wit...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864271Rashba control to minimize circuit cost of quantum Fourier algorithm in ballistic nanowires
https://medworm.com/658864270/rashba-control-to-minimize-circuit-cost-of-quantum-fourier-algorithm-in-ballistic-nanowires/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): A.H. Homid, M.R. Sakr, A.-B.A. Mohamed, M. Abdel-Aty, A.-S.F. ObadaAbstractThe presented work provides a new prospective of quantum computer hardware development through ballistic nanowires with Rashba effect. We address Rashba effect as a possible mechanism to realize novel qubit gates in nanowires. We apply our results to the design of a new quantum circuit for Fourier algorithm, which shows an improved quantum cost in terms of the number of gates. The current system can be successfully implemented to increase the production of quantum computer experimentally thanks to the absence of impurities. The introduced circuit will enhance the scope of experimental and theoretical research for the realization of...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864270Axial momentum for the relativistic Majorana particle
https://medworm.com/658864269/axial-momentum-for-the-relativistic-majorana-particle/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): H. ArodźAbstractThe Hilbert space of states of the relativistic Majorana particle consists of normalizable bispinors with real components, hence the usual momentum operator −i∇ can not be defined in this space. For this reason, we introduce the axial momentum operator, −iγ5∇ as a new observable for this particle. In the Heisenberg picture, the axial momentum contains a component which oscillates with the amplitude proportional to m/E, where E is the energy and m the mass of the particle. The presence of the oscillations discriminates between the massive and massless Majorana particle. Furthermore, we show how the eigenvectors of the axial momentum, called the axial plane waves, can be used as a ...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864269Noise-Induced Multilevel Landau-Zener Transitions: Density Matrix Investigation
https://medworm.com/658864268/noise-induced-multilevel-landau-zener-transitions-density-matrix-investigation/
Publication date: Available online 21 January 2019Source: Physics Letters AAuthor(s): I.F. Nyisomeh, M.E. Ateuafack, L.C. FaiAbstractThe generalised multilevel Landau-Zener problem is solved by applying the density matrix technique within the framework of nonstationary perturbation theory. The exact survival probability is achieved as a proof of the Brundobler-Elzer hypothesis [J. Phys. A: Math. Gen. 26, 1211 (1993)]. The effect of classical Gaussian noise is investigated by averaging the solution over the noise realisation. A generalised formula for slow noise-induced transition probability is obtained and found to agree exactly with all known results. Exact results are reported for the Demkov-Osherov model in the slow and fast noise limits. Thermal transition probabilities are obtained v...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864268Formation of intermediate coupling optical polarons and bipolarons in two-dimensional systems
https://medworm.com/658864252/formation-of-intermediate-coupling-optical-polarons-and-bipolarons-in-two-dimensional-systems/
Publication date: Available online 22 January 2019Source: Physics Letters AAuthor(s): S. Dzhumanov, P.J. Baimatov, Sh.T. Inoyatov, Sh.S. Djumanov, A.G. GulyamovAbstractThe formation of the optical polaron and bipolaron in two-dimensional (2D) systems is studied in the intermediate electron–phonon coupling regime. The total energies of the 2D polaron and bipolaron are calculated by using the Buimistrov–Pekar method of canonical transformations. The obtained results are compared with other existing results obtained by using the Feynman path integral method and the modified Lee–Low–Pines unitary transformation method. It is shown that the electron–phonon correlation significantly reduces the total energy of the 2D polaron in comparison with the energy of the strong coupling (adiabat...Physics Letters AjournalsTue, 22 Jan 2019 19:24:28 +0100658864252Edge intensity-based community measurement in complex networks
https://medworm.com/657970033/edge-intensity-based-community-measurement-in-complex-networks/
Publication date: Available online 18 January 2019Source: Physics Letters AAuthor(s): Hao LongAbstractCommunity is the dominant structure of complex networks. In recent years, community detection has become a heavily researched issue in network science, and many algorithms have been proposed to solve it. However, how to evaluate these algorithms and measure the strength of community structures is still an open problem. The modularity, as well as many of its variants, is widely used for this purpose, and maximizing such metrics is also a main approach to uncover communities, but this technique has a resolution limit problem in some cases, which means larger structures are favored over smaller ones. In this paper, we define the edge intensity to measure local density of network and propose a...Physics Letters AjournalsSun, 20 Jan 2019 20:23:39 +0100657970033Cooperation in the spatial public goods game with the second-order reputation evaluation
https://medworm.com/657970032/cooperation-in-the-spatial-public-goods-game-with-the-second-order-reputation-evaluation/
Publication date: Available online 18 January 2019Source: Physics Letters AAuthor(s): Yuetian Dong, Gang Hao, Juan Wang, Chen Liu, Chengyi XiaAbstractThe existence of reputation can significantly promote the level of cooperation within the human population. In the recent years, most of the researches were based on binary image score or first-order evaluation standard. In this paper, we propose a second-order reputation evaluation model, in which the individual's image score will change not only in accordance with his own strategy, but also the reputation value of neighbors. Individuals try to enhance their reputation to cooperate with the surrounding high-reputation individuals, and then becomes an influential individual in the population. The existence of this mechanism renders the indivi...Physics Letters AjournalsSun, 20 Jan 2019 20:23:39 +0100657970032Double Hopf bifurcation induces coexistence of periodic oscillations in a diffusive Ginzburg–Landau model
https://medworm.com/656889815/double-hopf-bifurcation-induces-coexistence-of-periodic-oscillations-in-a-diffusive-ginzburglanda/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Yanfei Du, Ben Niu, Yuxiao Guo, Jianquan LiAbstractWe perform bifurcation analysis in a complex Ginzburg–Landau system with delayed feedback under the homogeneous Neumann boundary condition. We calculate the amplitude death region, and it turns out that the boundary of the amplitude death region consists of two Hopf bifurcation curves with wave number zero. The existence conditions for double Hopf bifurcations are established. Taking the feedback strength and time delay as bifurcation parameters, normal forms truncated to the third order at double Hopf singularity are derived, and the unfolding near the critical points is given. The bifurcation diagram near the double Hopf bifurcation is drawn in the tw...Physics Letters AjournalsFri, 18 Jan 2019 12:09:26 +0100656889815SERS-signal optimised AgNPs-plated-ZnO nanoflower-like structure synthesised for sensing applications
https://medworm.com/656889811/sers-signal-optimised-agnps-plated-zno-nanoflower-like-structure-synthesised-for-sensing-application/
Publication date: Available online 17 January 2019Source: Physics Letters AAuthor(s): Tianhui Jiao, Felix Y.H. Kutsanedzie, Jing Xu, Annavaram Viswadevarayalu, Md Mehedi Hassan, Huanhuan Li, Yi Xu, Quansheng ChenAbstractAgNPs-plated-ZnO nanoflower (NFs)-like structures (Ag@ZnO NFs) with optimised signals were synthesised via wet chemical method at different temperatures (50 - 80 °C). The enhancement factors (EFs) computed for the resultant Ag@ZnO ranged between 2.36 - 8.46×107 obtained at the different temperatures using 4-aminothiophenol (4-ATP). The achieved EF results indicate Ag@ZnO synthesised at 50 °C gave the best enhancement. It was therefore selected, characterised and used to fabricate a SERS-based nanosensor for the detection of 2,4-dichlorophenoxyacetic acid (2,4-D) with a l...Physics Letters AjournalsFri, 18 Jan 2019 12:09:26 +0100656889811Transient thin film flow of nonlinear radiative Maxwell nanofluid over a rotating disk
https://medworm.com/656889810/transient-thin-film-flow-of-nonlinear-radiative-maxwell-nanofluid-over-a-rotating-disk/
Publication date: Available online 17 January 2019Source: Physics Letters AAuthor(s): Jawad Ahmed, Masood Khan, Latif AhmadAbstractIn this letter, a mathematical model for transient nature thin film flow of Maxwell nanofluid over a rotating disk is studied in the presence of a uniform magnetic field and non-linear thermal radiation. The Brownian motion and thermophoresis features due to nanofluid are captured by adopting the Buongiorno model. The prime emphasize is to explore the temperature field and nanoparticles volume fraction in nanofluid thin film flow. The reduced system of differential equations is solved numerically by finite difference based method namely bvp4c. The numerical outcomes regarding film thickness, Nusselt number, Sherwood number, velocity, temperature, and concentrat...Physics Letters AjournalsFri, 18 Jan 2019 12:09:26 +0100656889810Thermal properties of triangle nitrogen-doped graphene nanoribbons
https://medworm.com/656889809/thermal-properties-of-triangle-nitrogen-doped-graphene-nanoribbons/
Publication date: Available online 17 January 2019Source: Physics Letters AAuthor(s): Bing Yang, Dongbo Li, Liang Qi, Tianbo Li, Ping YangAbstractWe investigate the thermal properties of triangle nitrogen-doped graphene nanoribbons (TNGNs) with different nitrogen-doped concentrations (0.11% to 2.31%) at different temperatures (200K∼600K) using non-equilibrium molecular dynamics. The results show that the nitrogen atoms doped at the edge of the defect can increase the thermal conductivity of graphene nanoribbons, but with the increase of the nitrogen-doped concentrations from 0.11% to 2.31%, the thermal conductivity decreases sharply. In addition, nitrogen atoms reduces the sensitivity of the thermal conductivity to temperature. Besides, the thermal rectification is found, and it increase...Physics Letters AjournalsFri, 18 Jan 2019 12:09:26 +0100656889809Study of the q-Gaussian distribution with the scale index and calculating entropy by normalized inner scalogram
https://medworm.com/656889808/study-of-the-q-gaussian-distribution-with-the-scale-index-and-calculating-entropy-by-normalized-inne/
Publication date: Available online 17 January 2019Source: Physics Letters AAuthor(s): Mahmut Akıllı, Nazmi Yılmaz, K. Gediz AkdenizAbstractIn this paper, we discuss a method based on wavelet analysis for the study of the q-index of the Gaussian distribution. We derive q-index from the scale index, iscale, using the expression; q≡1+2iscale where iscale is a wavelet based tool for measuring the degree of aperiodicity of a dynamical system in the range of 0≤iscale≤1. We show that this expression gives consistent results with the numerical approach of q-Gaussian distribution which determines the degree of non-extensivity of a dynamical system in the range of 1<q<3. We also suggest a new entropy calculation method based on the normalized inner scalogram for studying the chaotic...Physics Letters AjournalsFri, 18 Jan 2019 12:09:26 +0100656889808The Role of CdCl2 Treatments and Annealing in the Formation of Sintered CdTe Nanocrystal Solar Cells
https://medworm.com/656889807/the-role-of-cdcl2-treatments-and-annealing-in-the-formation-of-sintered-cdte-nanocrystal-solar-cells/
Publication date: Available online 17 January 2019Source: Physics Letters AAuthor(s): G. Jain, A. Ahnood, A. Chanaewa, K. Fox, P. MulvaneyAbstractSolution processing of CdTe nanocrystals is a promising approach for the fabrication of low cost photovoltaic devices at low process temperatures. However despite the inherent advantages of this approach, the nanoscale physical mechanisms underlying the fabrication process are not well understood. Here we demonstrate that chemical treatment of CdTe nanoparticles leads to the production of a deep valence band edge. However, the removal of ligands also introduces sizable quantities of excess oxygen into the films in the form of TeO2, as proved by XPS. Thermal annealing of the CdTe films in air removes this excess oxygen and the TeO2 signal. Anneali...Physics Letters AjournalsFri, 18 Jan 2019 12:09:26 +0100656889807Heat and mass transfer analysis of time-dependent tangent hyperbolic nanofluid flow past a wedge
https://medworm.com/656528660/heat-and-mass-transfer-analysis-of-time-dependent-tangent-hyperbolic-nanofluid-flow-past-a-wedge/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): S.M. Atif, S. Hussain, M. SagheeAbstractThe candid intension of this article is to inspect the heat and mass transfer of a magnetohydrodynamic tangent hyperbolic nanofluid. The nanofluid flow has been assumed to be directed by a wedge on its way. In addition, the collective stimulus of the convective heating mode with thermal radiation is inspected. The governing set of PDEs is rendered into that of the coupled nonlinear ODEs. The resulting ordinary differential equations are then solved by the well known shooting technique for two different cases; the flow over a static wedge and flow over a stretching wedge. The impact of intricate physical parameters on the velocity, temperature and concentration profi...Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528660Stay-eat or run-away: Two alternative escape behaviors
https://medworm.com/656528659/stay-eat-or-run-away-two-alternative-escape-behaviors/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Shuai Zhang, Mingyong Liu, Xiaokang Lei, Yunke HuangAbstractPursuit-and-evasion behavior in groups of animals is a phenomenon that can be easily observed in nature. Immediate flight upon detection is a common but not exclusive response for prey with both stay-eat behavior and run-away behavior occur during the predation process. It remains unclear why these two contrasting survival tactics appear, what the triggering conditions are and what internal mechanisms are at play. Here we investigate the effect of energy level on the behavior of prey during predation. We find that (1) the optimal escape speed of prey is context-dependent rather than the fastest always producing the best chance of survival. (2) Th...Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528659Magnetic anisotropy of ferromagnetic metals in low-symmetry systems
https://medworm.com/656528658/magnetic-anisotropy-of-ferromagnetic-metals-in-low-symmetry-systems/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Yoshishige Suzuki, Shinji MiwaAbstractWe have constructed an analytic formula to treat the perpendicular magnetic anisotropy energy in ferromagnetic metals with low symmetry, such as C4V and C3V. We find that the anisotropy energy is proportional to a part of the expectation values of the orbital angular momentum and magnetic dipole operator. Although the result is similar to the model proposed by Laan (1998) [2], we have derived a concrete expression for the spin-flip virtual excitation process term, which can be dominant in atoms with small magnetic moments and/or small exchange splitting. Pt monatomic layer with proximity-induced spin polarization grown on Fe is an example of this. Other multilayer sys...Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528658Green's function approach to the impurity state in the Lieb lattice
https://medworm.com/656528657/greens-function-approach-to-the-impurity-state-in-the-lieb-lattice/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Rui ZhuAbstractWavefunction of an impurity attached to the Lieb lattice is considered by directly computing the Green's function (GF) for the nearest-neighbor tight-binding model. By replacing the lattice GF with a GF array including all the nine GFs defining on the three-atom unit cell of the Lieb lattice, an accurate and efficient numerical technique is developed. Agreement of both the real and imaginary components of the GF between numerical simulation of the lattice GF and continuum-space Fourier transformation is achieved in the whole resonant-energy range. Both results demonstrate that the wavefunction amplitude decays in a power-law pattern while the resonant energy is small and it decays in a patt...Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528657A special type of explosion of basin boundary
https://medworm.com/656528656/a-special-type-of-explosion-of-basin-boundary/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Guiqin Kong, Yongxiang ZhangAbstractWe study a special type of explosion of a basin boundary set in an archetypal oscillator. A typical feature is that the basin boundaries change the number of basins separating at the same time. Before the explosion, a basin boundary contains some Wada points of ten basins. After the explosion, the basin boundary contains some Wada points of eighteen basins. The underlying mechanism for the explosion is investigated by the heteroclinic tangency and Lambda lemma. Basin entropy and boundary basin entropy are also used to describe the nature of basins of attraction and the basin boundary explosion. (Source: Physics Letters A)Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528656Double Hopf bifurcation induces coexistence of periodic oscillations in a diffusive Ginzburg-Landau model
https://medworm.com/656528655/double-hopf-bifurcation-induces-coexistence-of-periodic-oscillations-in-a-diffusive-ginzburg-landau-/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Yanfei Du, Ben Niu, Yuxiao Guo, Jianquan LiAbstractWe perform bifurcation analysis in a complex Ginzburg-Landau system with delayed feedback under the homogeneous Neumann boundary condition. We calculate the amplitude death region, and it turns out that the boundary of the amplitude death region consists of two Hopf bifurcation curves with wave number zero. The existence conditions for double Hopf bifurcations are established. Taking the feedback strength and time delay as bifurcation parameters, normal forms truncated to the third order at double Hopf singularity are derived, and the unfolding near the critical points is given. The bifurcation diagram near the double Hopf bifurcation is drawn in the two-...Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528655Noncommutative geometry of the quantum clock
https://medworm.com/656528654/noncommutative-geometry-of-the-quantum-clock/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): S. Mignemi, N. UrasAbstractWe introduce a model of noncommutative geometry that gives rise to the uncertainty relations recently derived from the discussion of a quantum clock. We investigate the dynamics of a free particle in this model from the point of view of doubly special relativity and discuss the geodesic motion in a Schwarzschild background. (Source: Physics Letters A)Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528654Nonlinear analysis of an improved continuum model considering mean-field velocity difference
https://medworm.com/656528653/nonlinear-analysis-of-an-improved-continuum-model-considering-mean-field-velocity-difference/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Zihao Wang, Rongjun Cheng, Hongxia GeAbstractBased on the velocity gradient model, an extended continuum model with consideration of the mean-field velocity difference is proposed in this paper. By using the linear stability theory, the linear stability criterion of the new model is gained, which proved that mean-field velocity difference has significant influence on stability of traffic flow. The KdV–Burgers equation is derived by using non-linear analysis method and the evolution of density wave near the neutral stability line is explored. Numerical simulations are carried out how mean-field velocity difference affect the stability of traffic flow, and energy consumption is also studied for this new m...Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528653Input-to-state stability analysis for memristive BAM neural networks with variable time delays
https://medworm.com/656528652/input-to-state-stability-analysis-for-memristive-bam-neural-networks-with-variable-time-delays/
Publication date: Available online 16 January 2019Source: Physics Letters AAuthor(s): Yong Zhao, Jürgen Kurths, Lixia DuanAbstractIn this paper, we are concerned with input-to-state stability of a class of memristive bidirectional associative memory (BAM) neural networks with variable time delays. Based on a nonsmooth analysis and set-valued maps, some novel sufficient conditions are obtained for the input-to-state stability of such networks, which extended some known results as particular cases. Finally, a numerical example is presented to illustrate the feasibility and effectiveness of our results. (Source: Physics Letters A)Physics Letters AjournalsThu, 17 Jan 2019 17:12:52 +0100656528652On the Thomas–Fermi model at the Planck scale
https://medworm.com/655990309/on-the-thomasfermi-model-at-the-planck-scale/
Publication date: Available online 15 January 2019Source: Physics Letters AAuthor(s): Homa Shababi, Kamel OurabahAbstractMany quantum gravity theories predict a minimal length of the order of the Planck length. In this letter, the Thomas–Fermi model is reformulated by taking into account such a prescription. A generalized Thomas–Fermi equation is derived, that reduces to the usual one in the absence of a minimal length. As an application, the model is used to study the dielectric screening process. Estimations of the Fermi length are given for star interior. (Source: Physics Letters A)Physics Letters AjournalsWed, 16 Jan 2019 12:36:42 +0100655990309Editors
https://medworm.com/655990291/editors/
Publication date: 28 January 2019Source: Physics Letters A, Volume 383, Issue 6Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 16 Jan 2019 12:36:42 +0100655990291On the issue of zero point energy in Bose–Einstein condensates
https://medworm.com/654199776/on-the-issue-of-zero-point-energy-in-boseeinstein-condensates/
Publication date: Available online 11 January 2019Source: Physics Letters AAuthor(s): F.A. DeeneyAbstractFollowing on our earlier work in this area, here we examine in some detail the physical mechanism involved in the Bose–Einstein condensation process. In particular we emphasise the significance of the zero value of the chemical potential at and below the critical temperature. The molar zero-point energy (ZPE) for an ideal gas of He4 atoms in our new analysis is estimated and found to be very close to that calculated for an ideal Fermi gas of He3 atoms under the same conditions. This gives numerical support to our theory. We also show how the theory is consistent with the presence of a density maximum in liquid He4. (Source: Physics Letters A)Physics Letters AjournalsSat, 12 Jan 2019 14:12:25 +0100654199776Quantum shape effects and novel thermodynamic behaviors at nanoscale
https://medworm.com/654199773/quantum-shape-effects-and-novel-thermodynamic-behaviors-at-nanoscale/
We report also a torque due to quantum shape effects. Furthermore, we introduce isoformal, shape preserving, process which opens the possibility of a new generation of thermodynamic cycles operating at nanoscale with unique features.Graphical abstract (Source: Physics Letters A)Physics Letters AjournalsSat, 12 Jan 2019 14:12:25 +0100654199773On the issue of zero point energy in Bose-Einstein condensates
https://medworm.com/653844189/on-the-issue-of-zero-point-energy-in-bose-einstein-condensates/
Publication date: Available online 11 January 2019Source: Physics Letters AAuthor(s): F.A. DeeneyAbstractFollowing on our earlier work in this area, here we examine in some detail the physical mechanism involved in the Bose-Einstein condensation process. In particular we emphasise the significance of the zero value of the chemical potential at and below the critical temperature. The molar zero-point energy (ZPE) for an ideal gas of He4 atoms in our new analysis is estimated and found to be very close to that calculated for an ideal Fermi gas of He3 atoms under the same conditions. This gives numerical support to our theory. We also show how the theory is consistent with the presence of a density maximum in liquid He4. (Source: Physics Letters A)Physics Letters AjournalsFri, 11 Jan 2019 19:24:27 +0100653844189Benchmark study of the SF-MI phase transition of the Bose–Hubbard model with density-induced tunneling
https://medworm.com/653844188/benchmark-study-of-the-sf-mi-phase-transition-of-the-bosehubbard-model-with-density-induced-tunne/
Publication date: Available online 11 January 2019Source: Physics Letters AAuthor(s): Tao Wang, Tao YingAbstractThe Bose–Hubbard model (BHM) is a standard model which describes the quantum behavior of ultracold bosons in optical lattice. When tuning the model parameters, a quantum phase transition from superfluid (SF) phase to Mott insulating (MI) phase emerges. However, an extra tunneling process – the density-induced tunneling – is usually ignored in the standard BHM. Using process-chain method, we give a thorough study of the phase diagram of the BHM with density-induced tunneling in different particle density regions and spatial dimensions. We find the density-induced tunneling process can affect the SF-MI phase boundary dramatically, by suppressing the MI region and tune the tip...Physics Letters AjournalsFri, 11 Jan 2019 19:24:27 +0100653844188Large magnetoresistance and perfect spin filter effect in Fe doped SnS2 half-metallic monolayers: A first principles study
https://medworm.com/653844187/large-magnetoresistance-and-perfect-spin-filter-effect-in-fe-doped-sns2-half-metallic-monolayers-a-/
Publication date: Available online 11 January 2019Source: Physics Letters AAuthor(s): Yi Liu, Shaoqiang Guo, Jiangang Yu, Huicai ZhongAbstractIn this work, the spin-resolved transport properties of the Fe doped SnS2 monolayer devices have been investigated. The results show that the doping systems have the transport properties of negative differential resistance, large magnetoresistance effect and near 100% spin polarization effect when the magnetization directions of two electrodes are in parallel. Moreover, the mechanisms for the properties also have been discussed. The original reason of these results could be due to the half-metallic of the doping system. Our results imply that Fe doped SnS2 monolayer is a promising candidate for the future spintronic devices. (Source: Physics Letters ...Physics Letters AjournalsFri, 11 Jan 2019 19:24:27 +0100653844187Robust pulses for high fidelity non-adiabatic geometric gate operations in an off-resonant three-level system
https://medworm.com/653844186/robust-pulses-for-high-fidelity-non-adiabatic-geometric-gate-operations-in-an-off-resonant-three-lev/
Publication date: Available online 11 January 2019Source: Physics Letters AAuthor(s): Ying Yan, Jie Lu, Lin Wan, Joel MoserAbstractWe propose a method to design pulses in a resonant three-level system to enhance the robustness of non-adiabatic geometric gate operations. By optimizing the shape of the pulse envelope, we show that the gate operations are more robust against frequency detuning than they are with Gaussian and square pulses. Our method provides a way to design pulses that can be employed in a system where robustness against frequency variations or inhomogeneous broadening is required, and may be extended to ensure robustness against other physical imperfections such as intensity fluctuations and random noises. (Source: Physics Letters A)Physics Letters AjournalsFri, 11 Jan 2019 19:24:27 +0100653844186Enhancement of ablation rate and production of colloidal nanoparticles by irradiation of metals with nanosecond pulsed laser in presence of external electric field
https://medworm.com/653844185/enhancement-of-ablation-rate-and-production-of-colloidal-nanoparticles-by-irradiation-of-metals-with/
Publication date: Available online 11 January 2019Source: Physics Letters AAuthor(s): Hossein Mozaffari, Mohammad Hossein MahdiehAbstractThis paper presents the results of experimental study on the effect of electric field on the ablation rate during the nanosecond pulsed laser ablation of aluminum and copper in deionized water. The effect of electric field strength on the material removal rate and its mechanisms were investigated both in the electric field parallel and perpendicular to the laser beam path schemes. The ablation rate was estimated by measuring the dimensions of craters on the target induced by laser. The crater dimensions and optical properties of the produced colloidal nanoparticles were characterized by means of optical microscopy and UV–Vis absorption spectroscopy, res...Physics Letters AjournalsFri, 11 Jan 2019 19:24:27 +0100653844185Realizing reliable logic and memory function with noise-assisted Schmitt trigger circuits
https://medworm.com/653844184/realizing-reliable-logic-and-memory-function-with-noise-assisted-schmitt-trigger-circuits/
Publication date: Available online 11 January 2019Source: Physics Letters AAuthor(s): Lei Zhang, Wenbin Zheng, Fuhong Min, Aiguo SongAbstractSchmitt trigger is a comparator circuit with hysteresis, implemented by applying positive feedback to a noninverting input. Recently, it has been verified that noise under certain condition can help nonlinear circuit to realize reliable logical stochastic resonance (LSR). In this letter, we demonstrate that, without any modifications, Schmitt trigger can operate flexibly both as logic operation and latch operation in an optimal noise range. In traditional Schmitt trigger, the hysteresis is designed for resisting noise. In the new design, the hysteresis tends to enhance the LSR effect in Schmitt trigger with the help of noise and helps the system to pe...Physics Letters AjournalsFri, 11 Jan 2019 19:24:27 +0100653844184Engineering of carbon-based superlight spin filter with negative differential resistance
https://medworm.com/653309865/engineering-of-carbon-based-superlight-spin-filter-with-negative-differential-resistance/
Publication date: Available online 9 January 2019Source: Physics Letters AAuthor(s): Xi Zuo, Li Han, Heming Li, Xiaoteng Li, Jingfen Zhao, Bin Cui, De-Sheng LiuAbstractBased on density functional theory and non-equilibrium Green's function, we investigate the edge hydrogenation and oxidation effects on the spin transport of devices consisting of a zigzag C2N nanoribbon (ZC2NNR) embedded in zigzag graphene nanoribbons in parallel (P) and antiparallel (AP) spin configurations. The results show that device with edge hydrogenation exhibits dual spin filtering effect in AP spin configuration and obvious negative differential resistance in both P and AP spin configuration. By substituting oxygen for hydrogen as passivation atoms of ZC2NNR, the spin filtering efficiency is as high as 100% in the ...Physics Letters AjournalsThu, 10 Jan 2019 15:24:31 +0100653309865Magnetic properties of the Ashkin–Teller model on a hexagonal nanotube
https://medworm.com/652953568/magnetic-properties-of-the-ashkinteller-model-on-a-hexagonal-nanotube/
Publication date: Available online 7 January 2019Source: Physics Letters AAuthor(s): R.M. Francisco, J.P. SantosAbstractA new theoretical model for nanomagnets represented by the Ashkin–Teller model on a core-shell hexagonal nanotube is proposed. The Mean Field Theory from the Bogoliubov inequality is applied to study the magnetizations, phase boundaries and tricritical points. For a positive couplings system (ferromagnetic), first order and continuous phase transitions between the stable, metastable and unstable states are observed. For a negative core-shell coupling system, only continuous phase transitions between the stable and unstable states are observed. The phase diagram is presented to illustrate the different phases and transitions exhibited by the model. (Source: Physics Lette...Physics Letters AjournalsWed, 09 Jan 2019 20:30:27 +0100652953568Magnetic properties of the Ashkin-Teller model on a hexagonal nanotube
https://medworm.com/652415790/magnetic-properties-of-the-ashkin-teller-model-on-a-hexagonal-nanotube/
Publication date: Available online 7 January 2019Source: Physics Letters AAuthor(s): R.M. Francisco, J.P. SantosAbstractA new theoretical model for nanomagnets represented by the Ashkin-Teller model on a core-shell hexagonal nanotube is proposed. The Mean Field Theory from the Bogoliubov inequality is applied to study the magnetizations, phase boundaries and tricritical points. For a positive couplings system (ferromagnetic), first order and continuous phase transitions between the stable, metastable and unstable states are observed. For a negative core-shell coupling system, only continuous phase transitions between the stable and unstable states are observed. The phase diagram is presented to illustrate the different phases and transitions exhibited by the model. (Source: Physics Letters...Physics Letters AjournalsTue, 08 Jan 2019 16:12:26 +0100652415790Soliton lattices in the Gross–Pitaevskii equation with nonlocal and repulsive coupling
https://medworm.com/652415789/soliton-lattices-in-the-grosspitaevskii-equation-with-nonlocal-and-repulsive-coupling/
Publication date: Available online 7 January 2019Source: Physics Letters AAuthor(s): Hidetsugu SakaguchiAbstractSpatially-periodic patterns are studied in nonlocally coupled Gross–Pitaevskii equation. We show first that spatially periodic patterns appear in a model with the dipole–dipole interaction. Next, we study a model with a finite-range coupling, and show that a repulsively coupled system is closely related with an attractively coupled system and its soliton solution becomes a building block of the spatially-periodic structure. That is, the spatially-periodic structure can be interpreted as a soliton lattice. An approximate form of the soliton is given by a variational method. Furthermore, the effects of the rotating harmonic potential and spin-orbit coupling are numerically stud...Physics Letters AjournalsTue, 08 Jan 2019 16:12:26 +0100652415789Diffusive transport in highly corrugated channels
https://medworm.com/651159097/diffusive-transport-in-highly-corrugated-channels/
Publication date: Available online 4 January 2019Source: Physics Letters AAuthor(s): Fabio Cecconi, Valon Blakaj, Gabriele Gradoni, Angelo VulpianiAbstractDiffusion in waveguides with spatially modulated profiles is an important topic in modern electromagnetics and optics. Wave dynamics in the high-frequency asymptotics are governed by classical ray dynamics which can be characterised by looking at the diffusion of particles throughout the channel. We study the transport of particles (rays) in a channel with a sinusoidal profile at different values of the corrugation amplitude. We find that below a certain corrugation level the transport is ballistic, beyond this threshold, a diffusion-like behaviour emerges in the asymptotic limit of large times. In this regime particle transport slows do...Physics Letters AjournalsSat, 05 Jan 2019 22:03:32 +0100651159097Magnetoelectric coupling induced multistate magnetization
https://medworm.com/651159096/magnetoelectric-coupling-induced-multistate-magnetization/
Publication date: Available online 4 January 2019Source: Physics Letters AAuthor(s): Zhiguang Wang, Yanxi Li, Yaodong Yang, Jiefang Li, Dwight ViehlandAbstractComplex oxides provide an ideal playground for exploring the interplay among the fundamental degrees of freedom: structural (lattice), electronic (orbital and charge), and magnetic (spin). With trends toward device miniaturization, there is growing interest in combining electronic and magnetic properties into multifunctional thin-film materials for potential applications in novel versatile devices. Here, we report growth of ferromagnetic nanostructures on ferroelectric (1-x)[Pb(Mg1/3Nb2/3)O3]-x[PbTiO3] (PMN-PT) single crystals. With careful control of material composition and application of electric field direction and amplitude, we ...Physics Letters AjournalsSat, 05 Jan 2019 22:03:32 +0100651159096Scattering from a PEC strip buried in non-integer dimensional planar grounded dielectric slab by using Kobayashi potential method
https://medworm.com/651159095/scattering-from-a-pec-strip-buried-in-non-integer-dimensional-planar-grounded-dielectric-slab-by-usi/
Publication date: Available online 4 January 2019Source: Physics Letters AAuthor(s): Syed Faizan Javed, Musarat Abbas, Qaisar Abbas NaqviAbstractSolution for electromagnetic scattering from a perfect electric conducting strip buried in a planar grounded dielectric slab is determined by using the Kobayashi Potential Method. It is assumed that the dimension of mediums, above and within the slab, is non-integer in the direction normal to interface of the slab. The scattering problem is divided into two parts. In the first part, fields in the absence of strip are determined for plane wave excitation. In the second part, presence of the strip is taken into account. It has been assumed that spacings between the strip and interfaces of the slab are comparatively very larger than the wavelength of...Physics Letters AjournalsSat, 05 Jan 2019 22:03:32 +0100651159095Impact of core-periphery structure on cascading failures in interdependent scale-free networks
https://medworm.com/651159094/impact-of-core-periphery-structure-on-cascading-failures-in-interdependent-scale-free-networks/
Publication date: Available online 4 January 2019Source: Physics Letters AAuthor(s): Zhengcheng Dong, Meng Tian, Yuxin Lu, Jingang Lai, Ruoli Tang, Xin LiAbstractCore-periphery structure is a typical meso-scale structure in networks. Previous studies on core-periphery structure mainly focus on the improvement of detection methods, while the research on the impact of core-periphery structure on cascading failures in interdependent networks is still missing. Therefore, we investigate the cascading failures of interdependent scale-free networks with different core-periphery structures and coupling preferences in the paper. First, we introduce an evaluation index to calculate the goodness of core-periphery structure. Second, we propose a new scale-free network evolution model, which can genera...Physics Letters AjournalsSat, 05 Jan 2019 22:03:32 +0100651159094Relaxation in systems with hierarchical organization: Analytical derivation of the relaxation and dispersion functions
https://medworm.com/651159093/relaxation-in-systems-with-hierarchical-organization-analytical-derivation-of-the-relaxation-and-di/
We report a successful attempt to derive a closed-form expression for the relaxation function of a complex system by solving a set of coupled kinetic equations connecting the excitation/de-excitation rates to the number of particles (such as electrical charges, dipoles, etc.) in excited states. Our approach, originating from developments in dielectric and mechanical relaxation studies, allows the use of a unified treatment for a wide array of natural processes which often pose challenges to theoretical modeling. We use the notions that (i) a dipole represents any pair formed by a particle in an excited state (such as an energy level in optically excited molecules, or an electrode in dielectric spectroscopy) and its image in the ground state (or reference electrode), that (ii) coupling betw...Physics Letters AjournalsSat, 05 Jan 2019 22:03:32 +0100651159093Estimation of the disorder degree of the classical static noise using three entangled qubits as quantum probes
https://medworm.com/651159092/estimation-of-the-disorder-degree-of-the-classical-static-noise-using-three-entangled-qubits-as-quan/
Publication date: Available online 4 January 2019Source: Physics Letters AAuthor(s): Lionel Tenemeza Kenfack, Martin Tchoffo, Lukong Cornelius FaiAbstractThe paper investigates the estimation of the disorder degree of the classical static noise using three entangled qubits as quantum probes together with the tools of local quantum estimation theory. Three probing schemes namely common environment (CE), independent environments (IEs) and mixed environments (MEs) are investigated and the optimal initial state preparation of the probes taken as a partially depolarized GHZ state. The results show that: (i) the IEs probing scheme allows one to achieve better estimation precision compared to both MEs and CE schemes respectively; (ii) the higher is the initial amount of entanglement of the probes...Physics Letters AjournalsSat, 05 Jan 2019 22:03:32 +0100651159092Mechanism of resistance distribution properties in oxide-based resistance switching nanodevice
https://medworm.com/650255992/mechanism-of-resistance-distribution-properties-in-oxide-based-resistance-switching-nanodevice/
Publication date: Available online 2 January 2019Source: Physics Letters AAuthor(s): Ji-Hyun HurAbstractAlthough oxide-based resistive switching memory (OxRAM) is one of the strong next-generation high-capacity memory candidates, it has an unresolved problem that the higher the resistance levels, the larger the cycle-to-cycle resistance variabilities to be operated in multi-resistance level mode. In this paper, we develop a simple theory from the operating principles of OxRAMs that excellently matches with experiments both qualitatively and quantitatively. From the theory, we can finally understand the fundamental capabilities of multi-resistance level operation of OxRAMs, and how to improve the switching properties within that. (Source: Physics Letters A)Physics Letters AjournalsThu, 03 Jan 2019 22:43:25 +0100650255992Quantum information measures of the Aharonov–Bohm ring in uniform magnetic fields
https://medworm.com/650255991/quantum-information-measures-of-the-aharonovbohm-ring-in-uniform-magnetic-fields/
Publication date: Available online 2 January 2019Source: Physics Letters AAuthor(s): O. OlendskiAbstractShannon quantum information entropies Sρ,γ, Fisher informations Iρ,γ, Onicescu energies Oρ,γ and complexities eSO are calculated both in the position (subscript ρ) and momentum (γ) spaces for the azimuthally symmetric two-dimensional nanoring that is placed into the combination of the transverse uniform magnetic field B and the Aharonov–Bohm (AB) flux ϕAB and whose potential profile is modelled by the superposition of the quadratic and inverse quadratic dependencies on the radius r. The increasing intensity B flattens momentum waveforms Φnm(k) and in the limit of the infinitely large fields they turn to zero: Φnm(k)→0 at B→∞, what means that the position wave functions...Physics Letters AjournalsThu, 03 Jan 2019 22:43:25 +0100650255991Multiferroic behaviors of Co-doped Bi4NdTi3FeO15 ceramics
https://medworm.com/650255990/multiferroic-behaviors-of-co-doped-bi4ndti3feo15-ceramics/
Publication date: Available online 2 January 2019Source: Physics Letters AAuthor(s): Yahui Shu, Qingqing Ma, Zhenzhong Ding, Lin Cao, Xiaoqin Chen, Fujun Yang, Xiangbin ZengAbstractBy using a multicalcination procedure, Co-doped Bi4NdTi3Fe1-xCoxO15 (x=0.1, 0.3, 0.5 and 0.7) (Cox) ceramics were synthesized. The samples showed a single-phase (SP) Aurivillius structure containing four perovskite layers. Plate-like morphology of the grains which is related to the layered perovskite structure of the samples was clearly observed by SEM. The multiferroic properties of the samples at room temperature (RT) were demonstrated by dielectric, ferroelectric and magnetic measurements. With x ranging from 0.1 to 0.7, all the samples show RT multiferroic properties although there is no obvious regularity b...Physics Letters AjournalsThu, 03 Jan 2019 22:43:25 +01006502559902D magnetofluid models constructed by a priori imposition of conservation laws
https://medworm.com/647681896/2d-magnetofluid-models-constructed-by-a-priori-imposition-of-conservation-laws/
Publication date: Available online 28 December 2018Source: Physics Letters AAuthor(s): D.A. Kaltsas, G.N. ThroumoulopoulosAbstractMotivated by a geometric method employed for the derivation of the Nambu bracket for ideal two-dimensional incompressible hydrodynamics, we reconstruct the reduced magnetohydrodynamic (RMHD) model by a priori imposition of its conservation laws. It turns out that there exists a more general model that conserves the same quantities with RMHD. The noncanonical Hamiltonian and Nambu description of this generic system are derived and in addition a canonical description is formed by Clebsch-parameterizing the vorticity and the magnetic flux function. The method for the construction of the model is based on the imposition of the conservation laws as orthogonality cond...Physics Letters AjournalsSat, 29 Dec 2018 12:09:31 +0100647681896Andreev reflection in a patterned graphene nanoribbon superconducting heterojunction
https://medworm.com/647681895/andreev-reflection-in-a-patterned-graphene-nanoribbon-superconducting-heterojunction/
Publication date: Available online 28 December 2018Source: Physics Letters AAuthor(s): Chunxu Bai, Yanling Yang, Yongjin Jiang, H.X. YangAbstractIn the study, an improved superconducting heterojunction is made up of a zigzag graphene nanoribbon, which is patterned by a triangle and supports localized edge mode. Since all the localized edge modes stem from a pattern operation, the structure features of the pattern exert an enormous function on the coherent quantum transport. Especially, the patterned modes can enhance the Andreev reflection largely both in the ferromagenetic nanoribbon edge and the antiferromagetic nanoribbon edge. The spin resolved zero bias conductances, in sharp contrast to its counterpart in the infinite width superconducting heterojunction, exhibit the different depend...Physics Letters AjournalsSat, 29 Dec 2018 12:09:31 +0100647681895Early and late stages of K(m,n) compactons interaction
https://medworm.com/647681894/early-and-late-stages-of-kmn-compactons-interaction/
Publication date: Available online 28 December 2018Source: Physics Letters AAuthor(s): Alon Zilburg, Philip RosenauAbstractExploiting the finite span of compactons we use the K(m,n) Equation to develop an approximate description of early and late stages of their interaction. (Source: Physics Letters A)Physics Letters AjournalsSat, 29 Dec 2018 12:09:31 +0100647681894A new endocytic model based on the co-rotational grid method
https://medworm.com/647681893/a-new-endocytic-model-based-on-the-co-rotational-grid-method/
Publication date: Available online 28 December 2018Source: Physics Letters AAuthor(s): Kangyu Jia, Xiaohu LiuAbstractEndocytosis plays important roles in many cellular physiological processes, such as metabolism and immune. Many theoretical models have been proposed to study the endocytic process, but little has considered the tensile deformation of the membrane and the actin forces. In this paper, a new endocytic model is proposed based on the co-rotational grid method. Our model gives a direct estimation of the in-plane strain of the plasma membrane and provides a basis for the calculation of further scission process of the vesicle. The results fit well with experimental data in the literature. Moreover, it is suggested that the active forces of actin at the endocytic site is the main me...Physics Letters AjournalsSat, 29 Dec 2018 12:09:31 +0100647681893Editors
https://medworm.com/647681872/editors/
Publication date: 21 January 2019Source: Physics Letters A, Volume 383, Issue 5Author(s): (Source: Physics Letters A)Physics Letters AjournalsSat, 29 Dec 2018 12:09:31 +0100647681872Quantum regime for dielectric Cherenkov radiation and graphene surface plasmons
https://medworm.com/647311720/quantum-regime-for-dielectric-cherenkov-radiation-and-graphene-surface-plasmons/
Publication date: Available online 7 December 2018Source: Physics Letters AAuthor(s): Hesham Fares, Mohamed AlmokhtarAbstractIn this article, we propose a quantum regime for Cherenkov free-electron laser (CFEL) and surface plasmon polaritons (SPPs) excited in dielectric and multilayer graphene waveguides, respectively. This quantum regime is realized when the momentum spread induced in the interaction is smaller than the photon recoil. The discrete momentum exchange characterizing this interaction yields a significantly narrow single emission line. To determine the condition of the quantum regime, we derive an expression for the gain in the Cherenkov effect using a quantum mechanical treatment. It is assumed that the effective spread in momentum is due to the finite interaction length L (o...Physics Letters AjournalsFri, 28 Dec 2018 17:09:30 +0100647311720On the filamentation instability in degenerate relativistic plasmas
https://medworm.com/647311700/on-the-filamentation-instability-in-degenerate-relativistic-plasmas/
Publication date: Available online 27 December 2018Source: Physics Letters AAuthor(s): R.M. Goshadze, V.I. Berezhiani, Z. OsmanovAbstractThe filamentation instability of the electromagnetic (EM) beam in an underdense plasma with high level of degeneracy is examined by means of the momentum equation, continuity equation and Maxwell's equations. It has been demonstrated that the instability develops for weakly as well as strongly relativistic degenerate plasma and arbitrary strong amplitude of EM beams. (Source: Physics Letters A)Physics Letters AjournalsFri, 28 Dec 2018 17:09:30 +0100647311700Crystal structures of silicon-rich lithium silicides at high pressure
https://medworm.com/647311699/crystal-structures-of-silicon-rich-lithium-silicides-at-high-pressure/
Publication date: Available online 28 December 2018Source: Physics Letters AAuthor(s): Wenjing Li, Mingchun Lu, Eva Zurek, Xuedi Xu, Lulu Chen, Miao Zhang, Lili Gao, Xin Zhong, Jia Li, Xiaoming Zhou, Wenyan LiuAbstractSilicon (Si) is one of the most essential elements, as it is indispensable for modern electronic technology. The standard Si structure at ambient conditions is the cubic diamond structure, and it has an indirect band gap, which prevents it from being considered as a next-generation platform for semiconductor technologies. Therefore, the search for new allotropes of silicon has attracted great attention. Herein, first principles swarm-intelligence structure searches coupled with density-functional theory were performed to explore the stable high-pressure phases of silicon-rich...Physics Letters AjournalsFri, 28 Dec 2018 17:09:30 +0100647311699A general method to describe forgetting effect of memristors
https://medworm.com/644521267/a-general-method-to-describe-forgetting-effect-of-memristors/
Publication date: Available online 21 December 2018Source: Physics Letters AAuthor(s): Errui Zhou, Liang Fang, Binbin YangAbstractBuilding suitable memristor models is essential when memristors are attractive to researchers and play a vital role in fields such as neuromorphic computing. The forgetting effect, which is usually used to mimic forgetting process of biological synapses, should be considered during the modeling process. Several models have been proposed to describe forgetting effect. However, they have some deficiencies in describing forgetting effect, such as boundary problems. In this paper, a general method is presented to resolve these problems. The method is suitable for models that employ an inner state to describe the change of resistance and use a window function to cons...Physics Letters AjournalsSat, 22 Dec 2018 20:36:27 +0100644521267Effect of the twisting chirality configuration on the electromechanical behavior of multilayer superconducting tapes
https://medworm.com/644521265/effect-of-the-twisting-chirality-configuration-on-the-electromechanical-behavior-of-multilayer-super/
Publication date: Available online 21 December 2018Source: Physics Letters AAuthor(s): Wurui Ta, Yang Liu, Keyang Wang, Limei Liu, Yuanwen GaoAbstractSeeking a geometry that can withstand greater transverse loads based on the electromechanical material properties of high-temperature superconducting (HTS) tape is an effective way of improving the transport performance of HTS cables. The cabling method requires the determination of the optimum twist angle of the HTS tape for withstanding transverse loads. This paper investigates the critical current characteristics of HTS tapes under combined deformation. The limit range of the twist angle under the combined deformation is measured and the optimum twist angle of the HTS tape is determined. The results show that the twisting chirality configu...Physics Letters AjournalsSat, 22 Dec 2018 20:36:27 +0100644521265Observation of field induced anomalous quantum criticality in Ce0.6Y0.4NiGe2 compound
https://medworm.com/643962721/observation-of-field-induced-anomalous-quantum-criticality-in-ce06y04nige2-compound/
We report the results of our investigation of magnetization and heat capacity on a series of compounds Ce1-xYxNiGe2 (x=0.1,0.2 and 0.4) under the influence of external magnetic field. Our studies of the thermodynamic quantity -dM/dT on these compounds indicate that magnetic frustration persists in Ce0.9Y0.1NiGe2, as also reported for the parent compound CeNiGe2. The weak signature of this frustration is also noted in Ce0.8Y0.2NiGe2, whereas, it is suppressed in Ce0.6Y0.4NiGe2. Heat capacity studies on Ce0.9Y0.1NiGe2 and Ce0.8Y0.2NiGe2 indicate the presence of a new magnetic anomaly at high field which indicates that quantum criticality is absent in these compounds. However, for Ce0.6Y0.4NiGe2 such an anomaly is not noted. For this later compound, the magnetic field (H) and temperature (T...Physics Letters AjournalsFri, 21 Dec 2018 16:30:25 +0100643962721Characterization of dynamical measurement's uncertainty in a two-qubit system coupled with bosonic reservoirs
https://medworm.com/643589530/characterization-of-dynamical-measurements-uncertainty-in-a-two-qubit-system-coupled-with-bosonic-r/
Publication date: Available online 20 December 2018Source: Physics Letters AAuthor(s): Min-Nan Chen, Dong Wang, Liu YeAbstractWe study the dynamical characteristics of the entropy-based uncertainty with regard to a pair of incompatible measurements under a bipartite qubit-system suffering from quantum decoherence induced by hierarchical environments. How non-Markovian and Markovian environments affect the dynamical behaviors of the measurement's uncertainty is revealed. We prove that the measured uncertainty of interest demonstrates a non-monotonic behavior, viz., the amount will increase initially and subsequently oscillate periodically with the growth of time in a non-Markovian regime; On the contrary, the uncertainty will inflate firstly and monotonically decrease in a Markovian regime....Physics Letters AjournalsThu, 20 Dec 2018 21:09:30 +0100643589530On negative turbulence production phenomena in the shear layer of separating and reattaching flows
https://medworm.com/643589529/on-negative-turbulence-production-phenomena-in-the-shear-layer-of-separating-and-reattaching-flows/
Publication date: Available online 20 December 2018Source: Physics Letters AAuthor(s): A. Cimarelli, A. Leonforte, E. De Angelis, A. Crivellini, D. AngeliAbstractThe analysis of Direct Numerical Simulation data of the separating and reattaching flow over a blunt bluff body with sharp edges, reveals the presence of negative turbulence production mechanisms in the leading-edge shear layer. Contrary to what is commonly observed in fully developed turbulent flows, this phenomenon represents flow reversal of energy from the fluctuating field to the mean flow. The detailed study of the data reveals that at the origin of such mechanisms is a statistically positive relation between Reynolds shear stresses and vertical shear. We argue that such a positive relation is a result of large-scale interac...Physics Letters AjournalsThu, 20 Dec 2018 21:09:30 +0100643589529Novel nonlinear wave equation: Regulated rogue waves and accelerated soliton solutions
https://medworm.com/643033846/novel-nonlinear-wave-equation-regulated-rogue-waves-and-accelerated-soliton-solutions/
Publication date: Available online 18 December 2018Source: Physics Letters AAuthor(s): Abhik Mukherjee, Anjan KunduAbstractA new exactly solvable (1+1)-dimensional complex nonlinear wave equation exhibiting rich analytic properties has been introduced. A rogue wave (RW), localized in space–time like Peregrine RW solution, though richer due to the presence of free parameters is discovered. This freedom allows to regulate amplitude and width of the RW as needed. The proposed equation allows also an intriguing topology changing accelerated dark soliton solution in spite of constant coefficients in the equation. (Source: Physics Letters A)Physics Letters AjournalsWed, 19 Dec 2018 16:45:30 +0100643033846Experimental study on the effect of background music on pedestrian movement at high density
https://medworm.com/643033845/experimental-study-on-the-effect-of-background-music-on-pedestrian-movement-at-high-density/
Publication date: Available online 18 December 2018Source: Physics Letters AAuthor(s): Guang Zeng, Andreas Schadschneider, Jun Zhang, Shibo Wei, Weiguo Song, Rui BaAbstractAlthough crowding is often observed in large cities, it is still not known how to control it. Rhythm is a potential method to improve pedestrian flow. This paper investigates the effect of background music on pedestrian movement. Six experiments with different background rhythms and an experiment under normal condition (without any rhythm) are conducted to study the issue. Fundamental diagrams show that velocity and flow with background music at medium and high densities will be smaller than those under normal conditions. With music, stop-and-go behavior is more frequently observed due to a higher stopping headway and a ...Physics Letters AjournalsWed, 19 Dec 2018 16:45:30 +0100643033845Phononic Casimir corrections for Graphene resonator
https://medworm.com/643033844/phononic-casimir-corrections-for-graphene-resonator/
Publication date: Available online 18 December 2018Source: Physics Letters AAuthor(s): Y. Koohsarian, K. Javidan, A. ShirzadAbstractBy calculating a Casimir energy for the acoustic phonons of Graphene, we find some temperature-dependent corrections for the pretension of a Graphene sheet suspended on a trench. We obtain values of the order of few mN/m for these corrections in fully as well as doubly clamped Graphene on a narrow trench with one nanometer width, at room temperature. These values are considerable compared to the experimental values, and can increase the fundamental resonance frequency of the Graphene. The values of these corrections increase by increasing the temperature, and so they can be utilized for tuning the Graphene pretension. (Source: Physics Letters A)Physics Letters AjournalsWed, 19 Dec 2018 16:45:30 +0100643033844Editors
https://medworm.com/643033813/editors/
Publication date: 17 January 2019Source: Physics Letters A, Volume 383, Issue 4Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 19 Dec 2018 16:45:30 +0100643033813Microtransitions in a 2 − d load bearing hierarchical network
https://medworm.com/642477908/microtransitions-in-a-2d-load-bearing-hierarchical-network/
Publication date: Available online 17 December 2018Source: Physics Letters AAuthor(s): Anupama Roy, Neelima GupteAbstractWe identify the existence of microtransitions in the process of avalanche transmission on 2−d load bearing hierarchical networks. It has been seen in earlier work that typical realizations of this network exhibit a second order transition, whereas the critical realization of the network, shows a first order transition. The microtransitions can be used to predict the transition point for both cases. Microtransitions are also seen in the correlation function and scale in a similar way for the critical realisation. We compare the ratios of the peaks of the Fourier spectrum of the correlation function with the structure factor of the network to infer information about the ...Physics Letters AjournalsTue, 18 Dec 2018 12:09:25 +0100642477908Planck's experiment on gas mixing, Gibbs' paradox and the definition of entropy in statistical mechanics
https://medworm.com/642477907/plancks-experiment-on-gas-mixing-gibbs-paradox-and-the-definition-of-entropy-in-statistical-mecha/
Publication date: Available online 17 December 2018Source: Physics Letters AAuthor(s): A. PagliettiAbstractThe interpretation of entropy provided by statistical thermodynamics is not adequate to represent the thermodynamic entropy of the gas of noninteracting particles considered in this theory. Planck's thought experiment on reversible mixing and Gibbs' paradox provide perhaps the best-known evidence of this. The assumption that the internal energy of an ideal gas depends only on its temperature is introduced both in the kinetic theory of gases and in the classical thermodynamics. Such an assumption is no doubt adequate to deal with real gases at appropriately low pressures and high temperatures. However, the present paper shows that the same assumption implies that the entropy of an idea...Physics Letters AjournalsTue, 18 Dec 2018 12:09:25 +0100642477907Theoretical Study on UH4, UH8 and UH10 at High Pressure
https://medworm.com/642477906/theoretical-study-on-uh4-uh8-and-uh10-at-high-pressure/
Publication date: Available online 17 December 2018Source: Physics Letters AAuthor(s): Dong Wang, Han Zhang, Hai-Liang Chen, Jie Wu, Qing-Jun Zang, Wen-Cai LuAbstractStable structures of uranium hydrides at 0-550 GPa were studied using genetic algorithm (GA) combined with density functional theory calculations. We investigated two stoichiometries of U-H system, UH4 and UH10 at high pressure, and properties of UH4, UH8 and UH10. The study found that UH8 is the most stable phase at 100-550 GPa, UH4 is a stable phase at 100-550 GPa, and UH10 could become stable over 450 GPa. For UH10, the most phase is Fm3‾m, which was found to be a superconductor with the transition temperature Tc=51,21,12,10 and 15 K at 100, 200, 300, 400 and 550 GPa, respectively. (Source: Physics Letters A)Physics Letters AjournalsTue, 18 Dec 2018 12:09:25 +0100642477906Effects of ramification and connectivity degree on site percolation threshold on regular lattices and fractal networks
https://medworm.com/642477905/effects-of-ramification-and-connectivity-degree-on-site-percolation-threshold-on-regular-lattices-an/
Publication date: Available online 17 December 2018Source: Physics Letters AAuthor(s): Alexander S. Balankin, M.A. Martínez-Cruz, M.D. Álvarez-Jasso, M. Patiño-Ortiz, J. Patiño-OrtizAbstractThis Letter is focused on the impact of network topology on the site percolation. Specifically, we study how the site percolation threshold depends on the network dimensions (topological dand fractal D), degree of connectivity (quantified by the mean coordination number Z∞), and arrangement of bonds (characterized by the connectivity index Q also called the ramification exponent). Using the Fisher's containment principle, we established exact inequalities between percolation thresholds on fractal networks contained in the square lattice. The values of site percolation thresholds on some fractal la...Physics Letters AjournalsTue, 18 Dec 2018 12:09:25 +0100642477905Tunneling through bridges: Bohmian non-locality from higher-derivative gravity
https://medworm.com/641184633/tunneling-through-bridges-bohmian-non-locality-from-higher-derivative-gravity/
Publication date: Available online 14 December 2018Source: Physics Letters AAuthor(s): Gregory S. DuaneAbstractA classical origin for the Bohmian quantum potential, as that potential term arises in the quantum mechanical treatment of black holes and Einstein-Rosen (ER) bridges, can be based on 4th-order extensions of Einstein's equations. The required 4th-order extension of general relativity is given by adding quadratic curvature terms with coefficients that maintain a fixed ratio, as their magnitudes approach zero, with classical general relativity as a singular limit. If entangled particles are connected by a Planck-width ER bridge, as conjectured by Maldacena and Susskind, then a connection by a traversable Planck-scale wormhole, allowed in 4th-order gravity, describes such entanglemen...Physics Letters AjournalsSat, 15 Dec 2018 17:42:36 +0100641184633Translational cooling of doped nanocrystals by Raman pulses: Towards macroscopic quantum state
https://medworm.com/640627812/translational-cooling-of-doped-nanocrystals-by-raman-pulses-towards-macroscopic-quantum-state/
Publication date: Available online 13 December 2018Source: Physics Letters AAuthor(s): Tatiana A. Vovk, Semyon S. Rudyi, Andrei V. Ivanov, Evgeniy Y. Perlin, Yuri V. RozhdestvenskyAbstractOne of the most interesting problems of modern physics is the realization of nanoparticles in macroscopic quantum states, in which they behave as a quantum objects. These states can only be implemented at ultra-low translational temperatures that have not been achieved so far. Here we develop a novel method for optical cooling of CaF2:Yb3+ nanocrystals, which is based on the coherent population transfer induced in the impurity ions by ultraviolet Raman pulses. A doped nanocrystal localized in a radio-frequency trap is cooled due to the photon recoil from the pulses of varied intensity. The proposed method...Physics Letters AjournalsFri, 14 Dec 2018 13:39:26 +0100640627812Simulation of pedestrian evacuation strategies under limited visibility
https://medworm.com/640627811/simulation-of-pedestrian-evacuation-strategies-under-limited-visibility/
This study provides a new insight into the effect of different evacuation strategies on pedestrian evacuation, which is helpful for evacuees or organizers of public events to make an efficient evacuation plan under limited visibility. (Source: Physics Letters A)Physics Letters AjournalsFri, 14 Dec 2018 13:39:26 +0100640627811Image encryption using exclusive-OR with DNA complementary rules and double random phase encoding
https://medworm.com/640258320/image-encryption-using-exclusive-or-with-dna-complementary-rules-and-double-random-phase-encoding/
Publication date: Available online 12 December 2018Source: Physics Letters AAuthor(s): Dongming Huo, Ding-fu Zhou, Sheng Yuan, Shaoliang Yi, Luozhi Zhang, Xin ZhouAbstractWe propose an optical image encryption scheme based on the Deoxyribonucleic Acid (DNA) theory and the double random phase encoding (DRPE) technique. The piecewise linear chaotic map (PWLCM) is used to generate key images and random phase masks, and to determine DNA encoding rules. In order to achieve ultra-fast DNA encryption, we propose using an optical exclusive-OR (XOR) gate to achieve XOR operation in DNA encryption. Different plaintexts use different initial values of PWLCM, which are generated by Message Digest Algorithm 5 (MD5). The plaintext is encrypted by two rounds of DNA and then by DRPE to form a ciphertext. ...Physics Letters AjournalsThu, 13 Dec 2018 19:03:27 +0100640258320Structural and optical properties of cadmium magnesium zinc oxide (CdMgZnO) nanoparticles synthesized by sol-gel method
https://medworm.com/639685450/structural-and-optical-properties-of-cadmium-magnesium-zinc-oxide-cdmgzno-nanoparticles-synthesize/
Publication date: Available online 11 December 2018Source: Physics Letters AAuthor(s): Onyekachi Kalu, José Alberto Duarte Moller, Armando Reyes RojasAbstractNanoparticles of CdxMg0.12−xZn0.88O(0≤x≤0.02) were synthesized by a simple sol gel route with the combination of chelating agents. Effect of cadmium on the phase, structural, morphological and optical properties of the synthesized nanoparticles has been studied and reported by using x-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive x-ray (EDX), Fourier transform infrared spectroscopy(FTIR) and UV-Vis diffuse reflectance spectroscopy (UV-vis DRS). The crystal size, lattice parameters, unit cell volume, x-ray density, inter-planar distances and bond length were ...Physics Letters AjournalsWed, 12 Dec 2018 14:30:31 +0100639685450Spin-dependent thermoelectric effect in Co2Fe0.4Mn0.6Si thin film with perpendicular magnetic anisotropy
https://medworm.com/637784459/spin-dependent-thermoelectric-effect-in-co2fe04mn06si-thin-film-with-perpendicular-magnetic-anisot/
We report the anomalous Nernst effect in trilayers containing a thin film of the half-metallic ferromagnetic Heusler alloy Co2Fe0.4Mn0.6Si with perpendicular magnetic anisotropy. The structure is MgO/CFMS/Pd and we have studied the variation of anomalous Hall and Nernst effects as a function of CFMS and Pd thickness. The anomalous Nernst coefficient reaches 0.5 μV/K at room temperature and we have observed a strong dependence of the anomalous Nernst coefficient on the thickness of both layers. Our results indicate that inducing perpendicular magnetic anisotropy in a strongly spin-polarising Heusler alloy such as CFMS is very promising for new thermoelectric devices based on exploiting the anomalous Nernst effect. (Source: Physics Letters A)Physics Letters AjournalsSat, 08 Dec 2018 15:03:28 +0100637784459Quantum regime for the dielectric Cherenkov radiation and graphene surface plasmons
https://medworm.com/637784458/quantum-regime-for-the-dielectric-cherenkov-radiation-and-graphene-surface-plasmons/
Publication date: Available online 7 December 2018Source: Physics Letters AAuthor(s): Hesham Fares, Mohamed AlmokhtarAbstractIn this article, we propose a quantum regime for Cherenkov free-electron laser (CFEL) and surface plasmon polartions (SPPs) excited in dielectric and multilayer graphene waveguides, respectively. This quantum regime is realized when the momentum spread induced in the interaction is smaller than the photon recoil. The discrete momentum exchange characterizing this interaction yields a significantly narrow single emission line. To determine the condition of the quantum regime, we derive an expression for the gain in the Cherenkov effect using a quantum mechanical treatment. It is assumed that the effective spread in momentum is due to the finite interaction length L (o...Physics Letters AjournalsSat, 08 Dec 2018 15:03:28 +0100637784458A lattice Maxwell system with discrete space–time symmetry and local energy–momentum conservation
https://medworm.com/637400431/a-lattice-maxwell-system-with-discrete-spacetime-symmetry-and-local-energymomentum-conservatio/
Publication date: Available online 5 December 2018Source: Physics Letters AAuthor(s): Jianyuan Xiao, Hong Qin, Yuan Shi, Jian Liu, Ruili ZhangAbstractA lattice Maxwell system is developed with gauge-symmetry, symplectic structure and discrete space–time symmetry. Noether's theorem for Lie group symmetries is generalized to discrete group symmetries for the lattice Maxwell system. As a result, the lattice Maxwell system is shown to admit a discrete local energy–momentum conservation law corresponding to the discrete space–time symmetry. A lattice model that respects all local conservation laws and geometric structures is as good as and probably more preferable than standard models on continuous space–time. It can also be viewed as an effective algorithm for the governing differentia...Physics Letters AjournalsFri, 07 Dec 2018 20:18:27 +0100637400431Approximate conservation laws in the KdV equation
https://medworm.com/637400428/approximate-conservation-laws-in-the-kdv-equation/
Publication date: Available online 6 December 2018Source: Physics Letters AAuthor(s): Samer Israwi, Henrik KalischAbstractThe Korteweg–de Vries equation is known to yield a valid description of surface waves for waves of small amplitude and large wavelength. The equation features a number of conserved integrals, but there is no consensus among scientists as to the physical meaning of these integrals. In particular, it is not clear whether these integrals are related to the conservation of momentum or energy, and some researchers have questioned the conservation of energy in the dynamics governed by the equation. In this letter it is shown that while exact energy conservation may not hold, if momentum and energy densities and fluxes are defined in an appropriate way, then solutions of the...Physics Letters AjournalsFri, 07 Dec 2018 20:18:27 +0100637400428Influence of 120 MeV S9+ ion irradiation on structural, optical and morphological properties of zirconium oxide thin films deposited by RF sputtering
https://medworm.com/637400427/influence-of-120-mev-s9-ion-irradiation-on-structural-optical-and-morphological-properties-of-zirc/
Publication date: Available online 7 December 2018Source: Physics Letters AAuthor(s): Vishnu Chauhan, T. Gupta, Paramjit Singh, P.D. Sahare, N. Koratkar, Rajesh KumarAbstractThe calibrated and controlled swift heavy ions (SHI) beam irradiation generates defects which can cause modifications in various properties of the materials such as structural, optical, magnetic, morphological, and chemical etc. The passage of ion through the target material causes the nuclear energy losses (Sn) and electronic energy losses (Se). The Se dominates over Sn in SHI irradiation. In the present study, ZrO2 thin films were grown on silicon and glass substrate by using RF sputtering deposition technique. For the purpose of modifications induced by swift heavy ions, these films were irradiated by a 120 MeV S9+ ...Physics Letters AjournalsFri, 07 Dec 2018 20:18:27 +0100637400427Linear stability analysis of the natural convection in inclined rotating parallel plates
https://medworm.com/637400426/linear-stability-analysis-of-the-natural-convection-in-inclined-rotating-parallel-plates/
Publication date: Available online 7 December 2018Source: Physics Letters AAuthor(s): Diana Perez-Espejel, Ruben AvilaAbstractThe linear stability analysis of the natural convection in a rectangular tilted infinite cavity filled with a Boussinesq fluid subject to Coriolis force is presented. The bottom and top surfaces have fixed temperatures. Both unstable and stable thermal conditions are studied (heated from below and heated from above respectively). The rotation axis passes through the center and it is orthogonal to the hot and cold surfaces. The stability equations were solved using the Tau–Chebyshev spectral method. The critical Rayleigh number and critical wave number were obtained for several rotation rates and different orientation of convective oblique rolls in a range of incli...Physics Letters AjournalsFri, 07 Dec 2018 20:18:27 +0100637400426Computing Communities in Complex Networks Using the Dirichlet Processing Gaussian Mixture Model with Spectral Clustering
https://medworm.com/636821032/computing-communities-in-complex-networks-using-the-dirichlet-processing-gaussian-mixture-model-with/
Publication date: Available online 5 December 2018Source: Physics Letters AAuthor(s): Fang Hu, Yanhui Zhu, Jia Liu, Yalin JiaAbstractCommunity detection becomes a significant tool for the complex network analysis. The study of the community detection algorithms has received an enormous amount of attention. It is still an open question whether a highly accurate and efficient algorithm is found in most data sets. We propose the Dirichlet Processing Gaussian Mixture Model with Spectral Clustering algorithm for detecting the community structures. The combination of traditional spectral algorithm and new non-parametric Bayesian model provides high accuracy and quality. We compare the proposed algorithm with other existing community detecting algorithms using different real-world data sets and c...Physics Letters AjournalsThu, 06 Dec 2018 16:09:30 +0100636821032A lattice Maxwell system with discrete space-time symmetry and local energy-momentum conservation
https://medworm.com/636821031/a-lattice-maxwell-system-with-discrete-space-time-symmetry-and-local-energy-momentum-conservation/
Publication date: Available online 5 December 2018Source: Physics Letters AAuthor(s): Jianyuan Xiao, Hong Qin, Yuan Shi, Jian Liu, Ruili ZhangAbstractA lattice Maxwell system is developed with gauge-symmetry, symplectic structure and discrete space-time symmetry. Noether's theorem for Lie group symmetries is generalized to discrete group symmetries for the lattice Maxwell system. As a result, the lattice Maxwell system is shown to admit a discrete local energy-momentum conservation law corresponding to the discrete space-time symmetry. A lattice model that respects all local conservation laws and geometric structures is as good as and probably more preferable than standard models on continuous space-time. It can also be viewed as an effective algorithm for the governing differential equati...Physics Letters AjournalsThu, 06 Dec 2018 16:09:30 +0100636821031Ground-state properties of dilute one-dimensional Bose gas with three-body repulsion
https://medworm.com/636821030/ground-state-properties-of-dilute-one-dimensional-bose-gas-with-three-body-repulsion/
Publication date: Available online 5 December 2018Source: Physics Letters AAuthor(s): Volodymyr PastukhovAbstractWe determined perturbatively the low-energy universal thermodynamics of dilute one-dimensional bosons with the three-body repulsive forces. The final results are presented for the limit of vanishing potential range in terms of three-particle scattering length. An analogue of Tan's energy theorem for considered system is derived in generic case without assuming weakness of the interparticle interaction. We also obtained an exact identity relating the three-body contact to the energy density. (Source: Physics Letters A)Physics Letters AjournalsThu, 06 Dec 2018 16:09:30 +0100636821030Global versus local superintegrability of nonlinear oscillators
https://medworm.com/636821029/global-versus-local-superintegrability-of-nonlinear-oscillators/
Publication date: Available online 5 December 2018Source: Physics Letters AAuthor(s): Stephen C. Anco, Angel Ballesteros, Maria Luz GandariasAbstractLiouville (super)integrability of a Hamiltonian system of differential equations is based on the existence of globally well-defined constants of the motion, while Lie point symmetries provide a local approach to conserved integrals. Therefore, it seems natural to investigate in which sense Lie point symmetries can be used to provide information concerning the superintegrability of a given Hamiltonian system. The two-dimensional oscillator and the central force problem are used as benchmark examples to show that the relationship between standard Lie point symmetries and superintegrability is neither straightforward nor universal. In general, it...Physics Letters AjournalsThu, 06 Dec 2018 16:09:30 +0100636821029The effects of the electrochemical capacitance on the ac admittance phase of a quantum point contact
https://medworm.com/636821028/the-effects-of-the-electrochemical-capacitance-on-the-ac-admittance-phase-of-a-quantum-point-contact/
Publication date: Available online 5 December 2018Source: Physics Letters AAuthor(s): Jianzhuang Yin, Shuwei Chen, Li SongAbstractWe investigate the ac admittance of a quantum point contact (QPC) in quantum hall regime. Experiment data shows that the phase of the QPC admittance is not transmission independent. With the increasing of the QPC transmission, the phase increases in large magnetic field, but stays constant in small field. The theoretical works indicated that the Coulomb interaction between the counter-propagate channels is the main reason for the non-constant phase in large field. Besides this, we also studied the other types of Coulomb interactions. Especially, the Coulomb interaction between the channels across the QPC could make the sample behave like a capacitance and thus a...Physics Letters AjournalsThu, 06 Dec 2018 16:09:30 +0100636821028Stress annealing effect on the piezomagnetic coefficient of Fe–Al–B alloys
https://medworm.com/636246826/stress-annealing-effect-on-the-piezomagnetic-coefficient-of-fealb-alloys/
The objective is to evaluate the potential use of these alloys as smart materials of force sensors. The study comprises two alloys with compositions (Fe0.87Al0.13)98.4B1.6 (Al13) and (Fe0.82Al0.18)98.4B1.6 (Al18). The microstructure, hysteresis loops and B vs. σ|H were analyzed before and after the SA. Regarding the force sensitivity, the SA increased the piezomagnetic coefficient d33⁎ due the introduction of an extrinsic anisotropy in both Fe–Al–B alloys. Moreover, the stress range, in which the piezomagnetic coefficient d33⁎ is linear, is higher after the SA. Concerning the single phase (Fe0.87Al0.13)98.4B1.6 alloy, the force/pressure sensitivity and the linear stress range increase up to 16.8% and 47.1%, respectively. For the two phase (Fe0.82Al0.18)98.4B1.6 alloy, the increase...Physics Letters AjournalsWed, 05 Dec 2018 12:09:28 +0100636246826Azimuthal asymmetry of coherent Cherenkov radiation from a tilted bunch
https://medworm.com/636246824/azimuthal-asymmetry-of-coherent-cherenkov-radiation-from-a-tilted-bunch/
Publication date: Available online 4 December 2018Source: Physics Letters AAuthor(s): S.Yu. Gogolev, A.P. PotylitsynAbstractModern accelerator technologies may provide electron beams consisting of ultrashort bunches with transverse sizes, which are much larger than bunches with longitudinal sizes. The spectral-angular characteristics of coherent Cherenkov radiation (CChR) produced by the former type have thus been considered. We simulated the characteristics of CChR and those from a single charge on the basis of the polarisation current model, which allowed us to consider finite sizes for the target Cherenkov radiator. We calculated the angular distribution of the CChR from a bunch tilted by angle ψ, with respect to the velocity direction, with the assumption of a 3-D Gaussian charge dist...Physics Letters AjournalsWed, 05 Dec 2018 12:09:28 +0100636246824I–V characteristics and conductance of strained SWCNTs
https://medworm.com/636246823/iv-characteristics-and-conductance-of-strained-swcnts/
We present a new procedure to investigate the I–V characteristics and the conductance for strained SWCNTs. These electronic transport properties have been studied theoretically at zero temperature for zig-zag, armchair and chiral SWCNTs under the effect of the uniaxial tension and torsional strain. The analytical expression of the energy spectrum in the tight binding approximation has been used to calculate the induced current and the conductance through Landauer–Büttiker formalism. It is shown that the conductance for unstrained CNTs at initial values of the voltage can take discrete values which are equal to zero and 4 (e2/h) for semiconducting and conducting SWCNTs respectively. The emergence of the kinks in the I–V characteristics is due to the discrete electronic spectrum in th...Physics Letters AjournalsWed, 05 Dec 2018 12:09:28 +0100636246823Implications of spectral hole burning on the manipulation of spatial Goos–Hänchen shift in an atomic cell
https://medworm.com/635862906/implications-of-spectral-hole-burning-on-the-manipulation-of-spatial-gooshnchen-shift-in-an-ato/
We present a new scheme to report on Goos–Hänchen (GH) shift experienced by the Gaussian light beam interacting with an optical cavity filled with four-level sodium atomic medium in the spectral hole burning region with and without Doppler broadening effect. Theoretical atomic density-matrix formalism is employed to obtain the susceptibility of atomic medium while the stationary-phase-theory is used to compute the GH shift in the reflected and transmitted probe beams subjected to control fields. A steep normal slope of dispersion is observed with a maximum and zero probability of transmission and reflection coefficients, respectively, at the regions of the spectral holes burning. In the normal dispersion spectrum at the region of spectral hole burning, positive and negative GH shift is ...Physics Letters AjournalsTue, 04 Dec 2018 17:03:45 +0100635862906Strong entanglement criterion involving momentum weak values
https://medworm.com/635862893/strong-entanglement-criterion-involving-momentum-weak-values/
Publication date: Available online 3 December 2018Source: Physics Letters AAuthor(s): A. Valdés-Hernández, L. de la Peña, A.M. CettoAbstractIn recent years weak values have been used to explore interesting quantum features in novel ways. In particular, the real part of the weak value of the momentum operator has been widely studied, mainly in connection with Bohmian trajectories. Here we focus on the imaginary part and its role in relation with the entanglement of a bipartite system. We establish an entanglement criterion based on weak momentum correlations, that allows to discern whether the entanglement is encoded in the amplitude and/or in the phase of the wave function. Our results throw light on the physical role of the real and imaginary parts of the weak values, and stress the re...Physics Letters AjournalsTue, 04 Dec 2018 17:03:45 +0100635862893Path integrals with discarded degrees of freedom
https://medworm.com/635862892/path-integrals-with-discarded-degrees-of-freedom/
Publication date: Available online 3 December 2018Source: Physics Letters AAuthor(s): Luke M. ButcherAbstractWhenever variables ϕ=(ϕ1,ϕ2,…) are discarded from a system, and the discarded information capacity S(x) depends on the value of an observable x, a quantum correction ΔVeff(x) appears in the effective potential [1]. Here I examine the origins and implications of ΔVeff within the path integral, which I construct using Synge's world function. I show that the ϕ variables can be ‘integrated out’ of the path integral, reducing the propagator to a sum of integrals over observable paths x(t) alone. The phase of each path is equal to the semiclassical action (divided by ħ) including the same correction ΔVeff as previously derived. This generalises the prior results beyond the l...Physics Letters AjournalsTue, 04 Dec 2018 17:03:45 +0100635862892Stress annealing effect on the piezomagnetic coefficient of Fe-Al-B alloys
https://medworm.com/635862891/stress-annealing-effect-on-the-piezomagnetic-coefficient-of-fe-al-b-alloys/
The objective is to evaluate the potential use of these alloys as smart materials of force sensors. The study comprises two alloys with compositions (Fe0.87Al0.13)98.4B1.6 (Al13) and (Fe0.82Al0.18)98.4B1.6 (Al18). The microstructure, hysteresis loops and B vs. σ|H were analyzed before and after the SA. Regarding the force sensitivity, the SA increased the piezomagnetic coefficient d33⁎ due the introduction of an extrinsic anisotropy in both Fe-Al-B alloys. Moreover, the stress range, in which the piezomagnetic coefficient d33⁎ is linear, is higher after the SA. Concerning the single phase (Fe0.87Al0.13)98.4B1.6 alloy, the force/pressure sensitivity and the linear stress range increase up to 16.8% and 47.1%, respectively. For the two phase (Fe0.82Al0.18)98.4B1.6 alloy, the increase was...Physics Letters AjournalsTue, 04 Dec 2018 17:03:45 +0100635862891Doping-induced giant rectification and negative differential conductance (NDC) behaviors in zigzag graphene nano-ribbon junction
https://medworm.com/635862890/doping-induced-giant-rectification-and-negative-differential-conductance-ndc-behaviors-in-zigzag-g/
Publication date: Available online 3 December 2018Source: Physics Letters AAuthor(s): Huan-Yan Fu, Feng Sun, Ran Liu, Yu-Qing Suo, Jun-Jie Bi, Chuan-Kui Wang, Zong-Liang LiAbstractBy p-type and n-type doping on the electrode edges of V-notched zigzag graphene nano-ribbons (ZGNRs), four V-notched ZGNR-based PN-junctions are designed theoretically. The electronic transport properties of the doped and un-doped V-notched ZGNRs are studied applying non-equilibrium Green's function method combined with the density functional theory. The numerical results show that, the doped systems are less conductive than the un-doped system, because after doping the transition states become localized. To our surprise, the ZGNR-based PN-junctions do not show obvious rectification by purely doping the boron ato...Physics Letters AjournalsTue, 04 Dec 2018 17:03:45 +0100635862890Revisiting the admissibility of non-contextual hidden variable models in quantum mechanics
https://medworm.com/634526619/revisiting-the-admissibility-of-non-contextual-hidden-variable-models-in-quantum-mechanics/
Publication date: Available online 30 November 2018Source: Physics Letters AAuthor(s): Atul Singh Arora, Kishor Bharti, ArvindAbstractWe construct a non-contextual hidden variable model consistent with all the kinematic predictions of quantum mechanics (QM). The famous Bell–KS theorem shows that non-contextual models which satisfy a further reasonable restriction are inconsistent with QM. In our construction, we define a weaker variant of this restriction which captures its essence while still allowing a non-contextual description of QM. This is in contrast to the contextual hidden variable toy models, such as the one by Bell, and brings out an interesting alternate way of looking at QM. The results also relate to the Bohmian model, where it is harder to pin down such features. (Source: ...Physics Letters AjournalsSat, 01 Dec 2018 23:24:30 +0100634526619Directed LPA: Propagating labels in directed networks
https://medworm.com/634526618/directed-lpa-propagating-labels-in-directed-networks/
Publication date: Available online 30 November 2018Source: Physics Letters AAuthor(s): Xue LiAbstractIgnoring edge directionality and considering the graph as undirected is a common approach to detect communities in directed networks. However, it's not a meaningful way due to the loss of information captured by the edge property. Even if Leicht and Newman extended the original modularity to a directed version to address this issue, the problem of distinguishing the directionality of the edges still exists in maximizing modularity algorithms. To this direction, we extend one of the most famous scalable algorithms, namely label propagation algorithm (LPA), to a directed case, which can recognize the flow direction among nodes. To explore what properties the directed modularity should have, w...Physics Letters AjournalsSat, 01 Dec 2018 23:24:30 +0100634526618Generating Majorana modes in one-dimensional p-wave superconductor with second-neighbor couplings by periodic kicking
https://medworm.com/634526617/generating-majorana-modes-in-one-dimensional-p-wave-superconductor-with-second-neighbor-couplings-by/
Publication date: Available online 1 December 2018Source: Physics Letters AAuthor(s): X.P. Li, C.F. Li, L.C. Wang, L. ZhouAbstractGenerating many Majorana modes (MMs) within one single system is a constructive method for experimental observation of MMs in condensed-matter systems. In this paper, we show that by adding periodic δ-function kicks on the chemical potential, a large number of MMs can be generated in the one-dimensional p-wave superconductor system with second-neighbor couplings. The Floquet theory has been used to analyse the stroboscopic properties and the winding number can be used to characterize the topological properties. We have analyzed the influence of the kicking parameters and second-neighbor couplings on the topological phase transitions. (Source: Physics Letters A)Physics Letters AjournalsSat, 01 Dec 2018 23:24:30 +0100634526617Width dependent structural and electrical properties of zigzag ZnTe nanoribbons
https://medworm.com/633951919/width-dependent-structural-and-electrical-properties-of-zigzag-znte-nanoribbons/
Publication date: Available online 29 November 2018Source: Physics Letters AAuthor(s): Monoj Das, Bikash C. GuptaAbstractWe carry out density functional theory based investigation to understand the structural and electrical properties such as atomic structure, edge energy, band gap, and work function of zigzag ZnTe nanoribbons. It is found that the zigzag nanoribbons may be stabilized by passivating the edge atoms with Hydrogen, Oxygen or Fluorine atoms. Our study reflects that zigzag ZnTe nanoribbons with smaller width behave like semiconductor. However, they exhibit a transition from semiconducting phase to a metallic phase as width increases. A wide variation of band gap is obtained with respect to the choice of edge passivating elements. Work functions of all the nanoribbons are also e...Physics Letters AjournalsFri, 30 Nov 2018 19:18:28 +0100633951919Thermodynamic calculation of spin scaling functions
https://medworm.com/633951918/thermodynamic-calculation-of-spin-scaling-functions/
Publication date: Available online 29 November 2018Source: Physics Letters AAuthor(s): George RuppeinerAbstractCritical phenomena theory centers on the scaled thermodynamic potential per spin ϕ(β,h)=|t|pY(h|t|−q), with inverse temperature β=1/T, h=−βH, ordering field H, reduced temperature t=t(β), critical exponents p and q, and function Y(z) of z=h|t|−q. I discuss calculating Y(z) with the information geometry of thermodynamics. Scaled solutions are found to obtain with three admissible functions t(β): 1) t=e−Jβ, 2) t=β−1, and 3) t=βC−β, where J and βC are constants. For p=q, information geometry yields Y(z)=1+z2, consistent with the one-dimensional (1D) ferromagnetic Ising model. (Source: Physics Letters A)Physics Letters AjournalsFri, 30 Nov 2018 19:18:28 +0100633951918Parametric X-ray Radiation from powders
https://medworm.com/633951917/parametric-x-ray-radiation-from-powders/
Publication date: Available online 29 November 2018Source: Physics Letters AAuthor(s): V.I. Alekseev, A.N. Eliseyev, E. Irribarra, I.A. Kishin, A.S. Klyuev, A.S. Kubankin, R.M. Nazhmudinov, S.V. Trofymenko, P.N. ZhukovaAbstractParametric X-ray Radiation (PXR) produced in powders has been observed for the first time. PXR spectra were measured under observation angles of 150° and 180° during the interaction of relativistic 7 MeV electrons with a tungsten powder. All the PXR peaks that theoretically can be produced in the studied energy region were registered. The performed absolute comparison of the experiment with the PXR kinematical theory from randomly oriented crystallites showed a good accordance. (Source: Physics Letters A)Physics Letters AjournalsFri, 30 Nov 2018 19:18:28 +0100633951917While rotating while cloaking
https://medworm.com/633391811/while-rotating-while-cloaking/
Publication date: Available online 28 November 2018Source: Physics Letters AAuthor(s): Liliang Zhou, Shiyao Huang, Meng Wang, Run Hu, Xiaobing LuoAbstractInvisible optical and thermal cloaking have been explored as the typical demonstrations of the transformation optics and thermotics theory. However, the existing cloaks are realized by only one-coordinate transformation, and the cloaking layout, i.e. the form of electromagnetic wave/heat passing around the invisible region, is single for a long time. Here, we propose a new rotated thermal cloak which can unify the conventional cloaking and rotating together, and realize the while-rotating–while-cloaking effect. The required anisotropic thermal conductivity tensor is deduced from the new geometric mapping. Though rotated, the heat flux c...Physics Letters AjournalsThu, 29 Nov 2018 15:18:34 +0100633391811Exact and quasiclassical Green's functions of two-dimensional electron gas with Rashba–Dresselhaus spin–orbit interaction in parallel magnetic field
https://medworm.com/633391809/exact-and-quasiclassical-greens-functions-of-two-dimensional-electron-gas-with-rashbadresselhaus/
Publication date: Available online 28 November 2018Source: Physics Letters AAuthor(s): I.V. Kozlov, Yu.A. KolesnichenkoAbstractNew exact and asymptotical results for the one particle Green's function of 2D electrons with combined Rashba–Dresselhaus spin–orbit interaction in the presence of in-plane uniform magnetic field are presented. A special case that allows an exact analytical solution is also highlighted. To demonstrate the advantages of our approach we apply the obtained Green's function to calculation of electron density and magnetization. (Source: Physics Letters A)Physics Letters AjournalsThu, 29 Nov 2018 15:18:34 +0100633391809First-principles calculations of magnetic edge states in zigzag CrI3 nanoribbons
https://medworm.com/633391808/first-principles-calculations-of-magnetic-edge-states-in-zigzag-cri3-nanoribbons/
Publication date: Available online 28 November 2018Source: Physics Letters AAuthor(s): Wei Jiang, Shujing Li, Haitao Liu, Guo Lu, Fawei Zheng, Ping ZhangAbstractCrI3 monolayer has recently drawn much attention due to its two-dimensional long range ferromagnetic order. We find that CrI3 nanoribbons, which are strips of CrI3 monolayer, can be used as building blocks of nanodevices. In this paper, we studied the atomic and electronic structures of CrI3 zigzag nanoribbons by using first-principles calculations. CrI3 zigzag nanoribbons are also ferromagnet. Interestingly, edge states exist in the system and play an important role in their electronic structures. They dominate the band structures around Fermi level and can be tuned by edge atomic structures. The intrinsic ferromagnetism and rich ...Physics Letters AjournalsThu, 29 Nov 2018 15:18:34 +0100633391808Quantifying time irreversibility using probabilistic differences between symmetric permutations
https://medworm.com/633391807/quantifying-time-irreversibility-using-probabilistic-differences-between-symmetric-permutations/
Publication date: Available online 28 November 2018Source: Physics Letters AAuthor(s): Wenpo Yao, Wenli Yao, Jun Wang, Jiafei DaiAbstractTo simplify the quantification of time irreversibility, we employ order patterns instead of the raw multi-dimension vectors in time series, and considering the existence of forbidden permutation, we propose a subtraction-based parameter to measure probabilistic differences between symmetric permutations for time irreversibility. Two chaotic models, logistic and Henon systems, and reversible Gaussian process and their surrogate data are used to validate the time-irreversible measure, and time irreversibility of real-world epileptic EEGs from Nanjing General Hospital is detected by the parameter. Test results prove that it is promising to quantify time irre...Physics Letters AjournalsThu, 29 Nov 2018 15:18:34 +0100633391807Community Detection in Social Networks based on Improved Label Propagation Algorithm and Balanced Link Density
https://medworm.com/632979653/community-detection-in-social-networks-based-on-improved-label-propagation-algorithm-and-balanced-li/
Publication date: Available online 27 November 2018Source: Physics Letters AAuthor(s): Ehsan Jokar, Mohammad MoslehAbstractNowadays, community detection has been raised as one of the key research areas in the online social networks mining. One of the most common algorithms in this field is label propagation algorithm (LPA). Even though the LPA method has advantages such as simplicity in understanding and implementation, as well as linear time complexity, it has an important disadvantage of the uncertainty and instability in outcomes, that is, the algorithm detects and reports different combinations of communities in each run. This problem originates from the nature of random selection in the LPA method. In this paper, a novel method is proposed based on the LPA method and the inherent stru...Physics Letters AjournalsWed, 28 Nov 2018 20:21:49 +0100632979653Entanglement in four qubit states: Polynomial invariant of degree 2, genuine multipartite concurrence and one-tangle
https://medworm.com/632979651/entanglement-in-four-qubit-states-polynomial-invariant-of-degree-2-genuine-multipartite-concurrenc/
Publication date: Available online 27 November 2018Source: Physics Letters AAuthor(s): M.A. Jafarizadeh, M. Yahyavi, N. Karimi, A. HeshmatiAbstractCharacterization of the multipartite mixed state entanglement is still a challenging problem. This is due to the fact that the entanglement for the mixed states, in general, is defined by a convex-roof extension. That is the entanglement measure of a mixed state ρ of a quantum system can be defined as the minimum average entanglement of an ensemble of pure states. In this paper, we show that polynomial entanglement measures of degree 2 of even-N qubits X states is in the full agreement with the genuine multipartite (GM) concurrence. Then, we plot the hierarchy of entanglement classification for four qubit pure states and then using new invarian...Physics Letters AjournalsWed, 28 Nov 2018 20:21:49 +0100632979651A (2+1)-dimensional KdV equation and mKdV equation: symmetries, group invariant solutions and conservation laws
https://medworm.com/632979650/a-21-dimensional-kdv-equation-and-mkdv-equation-symmetries-group-invariant-solutions-and-conser/
Publication date: Available online 27 November 2018Source: Physics Letters AAuthor(s): Gangwei Wang, A.H. KaraAbstractIn this paper, we analyse the (2+1)-dimensional KdV and mKdV equations. Firtly, on the basis of the extended Lax pair, we derive these equations. Thereafter, the symmetry generators are determined followed by the application of the mCK method. Finally, conservation laws (including higher order) are studied. (Source: Physics Letters A)Physics Letters AjournalsWed, 28 Nov 2018 20:21:49 +0100632979650Hydrogen passivation tunes edge magnetism in the ZMoS2NR with a sulfur vacancy
https://medworm.com/632979649/hydrogen-passivation-tunes-edge-magnetism-in-the-zmos2nr-with-a-sulfur-vacancy/
Publication date: Available online 27 November 2018Source: Physics Letters AAuthor(s): J. Pan, X.Y. Zhou, R. Wang, J.H. He, L.J. Meng, J.G. HuAbstractWe performed density functional theory study on electronic structure, magnetic properties and stability of zigzag MoS2 nanoribbons with a S vacancy (ZMoS2NRs-VS) and considered their different edge passivation. The ZMoS2NR-VS systems are magnetic metals with ferromagnetic (FM) edge states. The magnetic moments are greatly influenced by the site of S vacancy and edge passivation because the vacancy and edge states significantly change the structure of the systems. Importantly, we can achieve distinct FM states such as both edge FM and single edge FM states in the ZMoS2NRs-VS by tuning edge passivated pattern. Additionally, edge passivation can...Physics Letters AjournalsWed, 28 Nov 2018 20:21:49 +0100632979649Implications of spectral-hole burning on the manipulation of spatial Goos–Hänchen shift in an atomic cell
https://medworm.com/632979648/implications-of-spectral-hole-burning-on-the-manipulation-of-spatial-gooshnchen-shift-in-an-ato/
We present a new scheme to report on Goos–Hänchen (GH) shift experienced by the Gaussian light beam incident at the plane optical interface filled with four-level sodium atomic medium in the spectral-hole burning region with and without Doppler broadening effect. Theoretical atomic density-matrix formalism is employed to obtain the susceptibility of atomic medium while the stationary-phase-theory is used to compute the GH shift in the reflected and transmitted probe beams subjected to control fields. A steep normal slope of dispersion is observed with a maximum and zero probability of transmission and reflection coefficients, respectively, at the regions of the spectral holes burning. In the normal dispersion spectrum at the region of spectral-hole burning, positive and negative GH shif...Physics Letters AjournalsWed, 28 Nov 2018 20:21:49 +0100632979648Terahertz planar lenses based on plasmonic metasurfaces
https://medworm.com/632979646/terahertz-planar-lenses-based-on-plasmonic-metasurfaces/
Publication date: Available online 28 November 2018Source: Physics Letters AAuthor(s): Chang Yang, Yun Shen, Yanqiang Xie, Qi Zhou, Xiaohua Deng, Juncheng CaoAbstractPlasmonic planar lenses on silicon substrate are designed to realize terahertz (THz) wave focusing. Super-unit-cells containing eight different resonant units are presented to construct eight concentric rings on the silicon substrate. By controlling of the position distribution of the resonant units, it is shown that focusing at 4.3 THz can be achieved. Moreover, due to that the eight units can steer THz wave and keep phase gradient in frequency range of 4.2 to 4.5 THz, the metalenses can realize broadband THz focusing. The results imply the potential applications in THz wave control devices of light collection and multi-chann...Physics Letters AjournalsWed, 28 Nov 2018 20:21:49 +0100632979646Relaxation of a dislocation in a nanocrystallite
https://medworm.com/632329634/relaxation-of-a-dislocation-in-a-nanocrystallite/
Publication date: Available online 27 November 2018Source: Physics Letters AAuthor(s): Vladimir P. ZhdanovAbstractExperimental studies of dislocations in nanoparticles are just beginning. The corresponding theoretical models are still lacking. In this context, the author analyzes relaxation of a dislocation in a nanoparticle. Mechanistically, this process is considered to occur primarily via dislocation drift induced by the stress-related image forces. Elementary dislocation displacements include the formation of a kink at one of the sides of the dislocation line, its diffusion along this line, and annihilation at the opposite side. For this mechanism, the dependence of the time of dislocation disappearance on the nanoparticle size has been identified. (Source: Physics Letters A)Physics Letters AjournalsTue, 27 Nov 2018 15:42:40 +0100632329634Conservation laws of nonconservative nonholonomic system based on Herglotz variational problem
https://medworm.com/632329633/conservation-laws-of-nonconservative-nonholonomic-system-based-on-herglotz-variational-problem/
Publication date: Available online 27 November 2018Source: Physics Letters AAuthor(s): Yi Zhang, Xue TianAbstractThe generalized variational principle of Herglotz type provides a variational method for describing nonconservative or dissipative processes. The purpose of this letter is to extend this variational principle to a first order linear nonholonomic system and study the conservation laws of the nonconservative nonholonomic system based on Herglotz variational problem. A new differential variational principle of the nonconservative nonholonomic system is proposed, which is based on Herglotz variational problem. And the differential equations of motion of the system are also obtained. Then, according to the condition for the invariance of the differential variational principle, the co...Physics Letters AjournalsTue, 27 Nov 2018 15:42:40 +0100632329633A general method for constructing vector integrable lattice systems
https://medworm.com/630806188/a-general-method-for-constructing-vector-integrable-lattice-systems/
Publication date: Available online 23 November 2018Source: Physics Letters AAuthor(s): Ruguang Zhou, Na Li, Jinyan ZhuAbstractA method for generating vector-value integrable analogies of integrable lattice systems or integrable differential-difference equations is presented. The basic ingredient of the method is to insert permutation matrices. We formulate the zero-curvature representations and Hamiltonian structures of the resulting vector lattice systems. The effectiveness of the method is illustrated using some examples such as the Volterra lattice, the Belov–Chaltikian lattice, the Ablowitz–Ladik lattice and the Heisenberg ferromagnet lattice. (Source: Physics Letters A)Physics Letters AjournalsSat, 24 Nov 2018 20:42:33 +0100630806188TBOR-shaped electro-optic modulator with dual output based on double-layer graphene
https://medworm.com/630157572/tbor-shaped-electro-optic-modulator-with-dual-output-based-on-double-layer-graphene/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Zhiquan Li, Landi Bai, Erdan Gu, Ruijie Xie, Xin Li, Wenchao LiAbstractWe proposed an electro-optic modulator with two-bus one-ring (TBOR) structure to improve the extinction ratio and reduce insert loss. It has a dual output compared with one-bus one-ring structure. In addition, double-layer graphene makes it possible for the modulation in the visible to mid-infrared wavelength range. It shows that this new electro-optic modulator can present two switching states well with low insertion loss, high absorption and high extinction ratio. At λ=1550 nm, when the switching states are based on the chemical potential, μc=0.38 eV and μc=0.4 eV, the insertion losses of both output ports are less than 2 dB, ...Physics Letters AjournalsFri, 23 Nov 2018 16:24:35 +0100630157572Cavitation occurring in capillary tubes
https://medworm.com/630157570/cavitation-occurring-in-capillary-tubes/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Steve Q. CaiAbstractSurface etches caused by cavitation often occur behind the blade of a rapidly rotating propeller or on a vibrating surface where liquid is subjected to suddenly reduced or oscillating saturation pressure. This phenomenon has never been reported in a continuous capillary pipe in which flow pressure varied gently without injection of external radiation energy. On the other aspect, acoustically tinkling signals were recognized decades ago during operation of the oscillation capillary heat pipe, but lacking of vigorous scientific understanding of the root causes. In this article, we report cavitation and its surface etches in meandering capillary tubes with the inner diameter of 1.8 mm. N...Physics Letters AjournalsFri, 23 Nov 2018 16:24:35 +0100630157570A new model equation for nonlinear Rossby waves and some of its solutions
https://medworm.com/630157568/a-new-model-equation-for-nonlinear-rossby-waves-and-some-of-its-solutions/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Quansheng Liu, Ruigang Zhang, Liangui Yang, Jian SongAbstractIn this paper, we investigate the (2+1) dimensional nonlinear Rossby waves under non-traditional approximation. Using the asymptotic methods of multiple scales and weak nonlinear perturbation expansions, we derive a new modified Zakharov-Kuznetsov equation from the barotropic potential vorticity equation with the complete Coriolis parameter, the topography and the dissipation. Based on the new auxiliary equation method, new exact solutions of the new mZK equation are obtained when the dissipation is absent. However, the new auxiliary equation method fails to solve the new mZK equation with the dissipative term. Therefore, the weak nonlinear met...Physics Letters AjournalsFri, 23 Nov 2018 16:24:35 +0100630157568Electron injection in laser wake-field acceleration by using near critical layers
https://medworm.com/629503345/electron-injection-in-laser-wake-field-acceleration-by-using-near-critical-layers/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Saeed Mirzanejhad, Maisam TaghipourAbstractA method for enhancing trapped electrons in the laser wake-field acceleration in dilute plasma is proposed. In this method, a thin layer with near critical density is placed in front of the dilute plasma. Upon interaction of this layer with a short and high power laser pulse, a relatively large number of layer electrons are injected in dilute plasma. Some of these electrons are trapped in the wake-field of transmitted laser pulse. Particle in cell simulation is used to demonstrate this method. Simulations showed that in addition to increasing the number of trapped electrons, this mechanism also reduces the energy broadening. (Source: Physics Letters A)Physics Letters AjournalsThu, 22 Nov 2018 12:09:43 +0100629503345Adsorption of CO gas molecules on zigzag BN/AlN nanoribbons for nano sensor applications
https://medworm.com/629503344/adsorption-of-co-gas-molecules-on-zigzag-bnaln-nanoribbons-for-nano-sensor-applications/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Rachana Yogi, Neeraj K. JaiswalAbstractFirst-principle calculations have been performed to study the sensing of CO gas in various considered configurations. The adsorption of CO on zigzag BN nanoribbon (ZBNNR) and zigzag AlN nanoribbon (ZAlNNR) was modelled in five different possibilities. The effect of CO adsorption is to reduce the band gap in both types (BN/AlN) of the nanoribbons. Interestingly, a finite magnetic moment (0.96 μB for ZBNNR and 0.687 μB for ZAlNNR) has been obtained which depends upon the adsorption configuration of CO. Half-metallicity was also observed upon selective CO adsorption on ZAlNNR irrespective of the ribbon width. Present findings suggest that CO gas molecules could be de...Physics Letters AjournalsThu, 22 Nov 2018 12:09:43 +0100629503344Enhancement of pupil-masked wavelength-scale gas-filled flat acoustic lens based on anomaly apodization effect
https://medworm.com/629503343/enhancement-of-pupil-masked-wavelength-scale-gas-filled-flat-acoustic-lens-based-on-anomaly-apodizat/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Constanza Rubio, Daniel Tarrazó-Serrano, Oleg V. Minin, Antonio Uris, Igor V. MininAbstractIn this letter, the improvement in focus by the use of a pupil mask produced in an acoustic mesoscale cuboid particle filled with CO2 is reported. Thereby, the result shows that the pupil mask increases the sound intensity and also increases the resolution (or a reduction of the full width at half maximum, FWHM) in focus compared to the non-masked one. These results are important because they confirm the effect of abnormal amplitude apodization for a one-wavelength dimension acoustic lens and demonstrate that it is possible to improve sound focusing of a cuboid gas-filled lens with one wavelength dimension. This i...Physics Letters AjournalsThu, 22 Nov 2018 12:09:43 +0100629503343Laplace transform approach for the dynamics of N qubits coupled to a resonator
https://medworm.com/629503342/laplace-transform-approach-for-the-dynamics-of-n-qubits-coupled-to-a-resonator/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Mirko Amico, Oleg L. Berman, Roman Ya. KezerashviliAbstractAn approach to use the method of Laplace transform for the perturbative solution of the Schrödinger equation at any order of the perturbation for a system of N qubits coupled to a cavity with n photons is suggested. We investigate the dynamics of a system of N superconducting qubits coupled to a common resonator with time-dependent coupling. To account for the contribution of the dynamical Lamb effect to the probability of excitation of the qubit, we consider counter-rotating terms in the qubit-photon interaction Hamiltonian. As an example, we illustrate the method for the case of two qubits coupled to a common cavity. The perturbative solutions...Physics Letters AjournalsThu, 22 Nov 2018 12:09:43 +0100629503342Linearizable boundary value problems for the nonlinear Schrödinger equation in laboratory coordinates
https://medworm.com/629503341/linearizable-boundary-value-problems-for-the-nonlinear-schrdinger-equation-in-laboratory-coordinat/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Katelyn Plaisier Leisman, Gino Biondini, Gregor KovacicAbstractBoundary value problems for the nonlinear Schrödinger equation on the half line in laboratory coordinates are considered. A class of boundary conditions that lead to linearizable problems is identified by introducing appropriate extensions to initial-value problems on the infinite line, either explicitly or by constructing a suitable Bäcklund transformation. Various soliton solutions are explicitly constructed and studied. (Source: Physics Letters A)Physics Letters AjournalsThu, 22 Nov 2018 12:09:43 +0100629503341Spectral engineering and tunable thermoelectric behavior in a quasiperiodic ladder network
https://medworm.com/629503340/spectral-engineering-and-tunable-thermoelectric-behavior-in-a-quasiperiodic-ladder-network/
Publication date: Available online 22 November 2018Source: Physics Letters AAuthor(s): Amrita Mukherjee, Atanu NandyAbstractDouble-stranded quasiperiodic copper mean arrangement has been studied in respect of its electronic property and thermoelectric signature. The two-arm network is demonstrated by a tight-binding Hamiltonian. The eigenspectrum of such aperiodic mesh that does not convey translational invariance, is significantly dependent on the parameters of the Hamiltonian. It is observed that specific correlation between the parameters obtained from the commutation relation between the on-site energy and overlap integral matrices can eventually modify the spectral nature and generate absolutely continuous energy spectrum. This part is populated by atypical extended states that has a ...Physics Letters AjournalsThu, 22 Nov 2018 12:09:43 +0100629503340Molecular dynamics simulations on the effect of nanovoid on shock-induced phase transition in uranium nitride
https://medworm.com/629080850/molecular-dynamics-simulations-on-the-effect-of-nanovoid-on-shock-induced-phase-transition-in-uraniu/
Publication date: Available online 19 November 2018Source: Physics Letters AAuthor(s): Y.L. Li, J. Cai, D. MoAbstractThe Angular-Dependent Potential (ADP) proposed by Tseplyaev et al. was used to study the structural behavior of uranium nitride (UN) under shock pressure by molecular dynamics (MD) simulations. Based on the calculations of shock velocity US and particle velocity UP, the results show that a pressure-induced phase transition of Fm−3m→R−3m structure in UN occurs at 35 GPa, and it agrees well with experimental results of 30–32 GPa. We also considered the effect of nanovoid on the phase transition of UN crystal from Fm−3m to R−3m structure. It is found that the pressure of phase transition decreases with the increasing nanovoid diameter. The phase transition takes pla...Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080850Can freestanding Xene monolayers behave as excitonic insulators?
https://medworm.com/629080849/can-freestanding-xene-monolayers-behave-as-excitonic-insulators/
Publication date: Available online 19 November 2018Source: Physics Letters AAuthor(s): Matthew N. Brunetti, Oleg L. Berman, Roman Ya. KezerashviliAbstractWe predict a phase transition in freestanding monolayer Xenes from the semiconducting phase to the excitonic insulating (EI) phase can be induced by reducing an external electric field below some critical value which is unique to each material. The splitting of the conduction and valence bands due to spin–orbit coupling at non-zero electric fields leads to the formation of A and B excitons in the larger or smaller band gap, with correspondingly larger or smaller binding energies. Our calculations show the coexistence of the semiconducting phase of A excitons with the EI phase of B excitons for a particular range of electric field. The d...Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080849Dynamical current–current correlation in two-dimensional parabolic Dirac systems
https://medworm.com/629080848/dynamical-currentcurrent-correlation-in-two-dimensional-parabolic-dirac-systems/
Publication date: Available online 19 November 2018Source: Physics Letters AAuthor(s): Chen-Huan WuAbstractWe theoretically investigate the current–current correlation of the two-dimensional (2D) parabolic Dirac system in hexogonal lattice. The analytical expressions of the random phase approximation (RPA) susceptibility, Ruderman–Kittel–Kasuya–Yosida (RKKY) Hamiltonian, and the diamagnetic orbital susceptibility in noninteracting case base on the density–density or current–current correlation function are derived and quantitatively analyzed. In noninteracting case, the dynamical polarization within RPA, and spin transverse susceptibility as well as the RKKY interaction (when close to the half-filling) are related to the current–current response in the 2D parabolic Dirac syst...Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080848Spin-orbital coupling and magnetic properties of Ir-based double perovskites with different 5dn (n = 3, 4, 5) states
https://medworm.com/629080847/spin-orbital-coupling-and-magnetic-properties-of-ir-based-double-perovskites-with-different-5dn-n-/
Publication date: Available online 19 November 2018Source: Physics Letters AAuthor(s): Yong-Feng Li, Kai-Cheng Zhang, Yong LiuAbstractWe have investigated the spin and orbital moments of Ir-based double perovskites with 5dn (n = 3, 4, 5) states by local spin-density approximation with spin-orbital coupling and Hubbard correlation (LSDA+SOC+U). Our calculations reveal that the ratio of orbital to spin momentum Lz/Sz approaches to certain values for the double perovskites with different 5dn (n = 3, 4, 5) shell fillings. Based on d orbits, a spin-orbital coupling model with exchange splitting is proposed and it can well describe the ratio of angular momentums for the compounds. Our model calculations reveal that Lz/Sz is determined by the exchange splitting, spin-orbital coupling as well as t...Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080847Classifying the ground-state phases of spin–orbit coupled spin-2 Bose–Einstein condensate in momentum space
https://medworm.com/629080846/classifying-the-ground-state-phases-of-spinorbit-coupled-spin-2-boseeinstein-condensate-in-mom/
Publication date: Available online 20 November 2018Source: Physics Letters AAuthor(s): Ji-Guo Wang, Wei Wang, Shi-Jie YangAbstractThe ground-state phases of two-dimensional spin-2 Bose–Einstein condensate with Rashba spin–orbit coupling are studied. For the equal strengths of the density-density interaction and the spin-exchange interaction, we classify the ground-state phases into four types of stable phases with spin–orbit coupling and spin singlet-pairing interaction in momentum space, i.e., the ring phase, the stripe phase, the triangular phase and the square phase. With increasing the spin–orbit coupling strength, the system undergoes a sequence phase transitions from the ring phase to the stripe phase, and to the square phase for the attractive spin singlet-pairing interactio...Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080846General N-solitons and their dynamics in several nonlocal nonlinear Schrödinger equations
https://medworm.com/629080845/general-n-solitons-and-their-dynamics-in-several-nonlocal-nonlinear-schrdinger-equations/
Publication date: Available online 20 November 2018Source: Physics Letters AAuthor(s): Jianke YangAbstractGeneral N-solitons in three recently-proposed nonlocal nonlinear Schrödinger equations are presented. These nonlocal equations include the reverse-space, reverse-time, and reverse-space–time nonlinear Schrödinger equations, which are nonlocal reductions of the Ablowitz–Kaup–Newell–Segur (AKNS) hierarchy. It is shown that general N-solitons in these different equations can be derived from the same Riemann–Hilbert solutions of the AKNS hierarchy, except that symmetry relations on the scattering data are different for these equations. This Riemann–Hilbert framework allows us to identify new types of solitons with novel eigenvalue configurations in the spectral plane. Dynamic...Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080845Spin orbit coupled Bose Einstein condensate in a two dimensional bichromatic optical lattice
https://medworm.com/629080844/spin-orbit-coupled-bose-einstein-condensate-in-a-two-dimensional-bichromatic-optical-lattice/
Publication date: Available online 20 November 2018Source: Physics Letters AAuthor(s): Z. OztasAbstractWe numerically investigate the localization of Bose Einstein condensate (BEC) with spin orbit coupling in a two dimensional bichromatic optical lattice. We study localization in weakly interacting and non-interacting regimes. The existence of stationary localized states in the presence of spin–orbit and Rabi couplings has been confirmed. We find that spin orbit coupling favors localization, whereas Rabi coupling has a slight delocalization effect. (Source: Physics Letters A)Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080844Novel design for bifurcation control in a delayed fractional dual congestion model
https://medworm.com/629080843/novel-design-for-bifurcation-control-in-a-delayed-fractional-dual-congestion-model/
Publication date: Available online 20 November 2018Source: Physics Letters AAuthor(s): Chengdai Huang, Tongxing Li, Liming Cai, Jinde CaoAbstractThis letter puts forward an ingenious feedback control method with parametric delay to manipulate bifurcation control for a delayed fractional dual congestion model. By employing time delay as a bifurcation parameter, the local dynamics involving stability and Hopf bifurcation is examined. The control efforts are realized with or without time delay in the strength of feedback control. It suggests that the stability performance is consumedly elevated by exploiting the parametric delay feedback controller, yet Hopf bifurcation engenders ahead of time in the event of the absence the controller. Moreover, the impact of the order or linear feedback gai...Physics Letters AjournalsWed, 21 Nov 2018 17:09:32 +0100629080843Self-organization of ultra-thin uranium film
https://medworm.com/627202937/self-organization-of-ultra-thin-uranium-film/
Publication date: Available online 16 November 2018Source: Physics Letters AAuthor(s): Xianggui Li, Shujing Li, Menglei Li, Mei Zhou, Fawei Zheng, Ping ZhangAbstractWe have studied the adsorption behaviors of uranium (U) atoms coated graphene at different coverage ratios using first-principles calculations. Isolated U atom is demonstrated to be more likely to stay on the hollow site of graphene with a large adsorption energy of 2.80 eV and high magnetic moment of 5.07 μB. It seems that two U atoms tend to adsorb on the nearest neighbor hollow sites of graphene. As the concentration of U atom increases, no U-dimer or U-cluster appears with increasing coverage ratio. In the case of coverage ratio of 2/3, U atoms on graphene is the most stable configuration, where each U atoms are uniformly-...Physics Letters AjournalsSun, 18 Nov 2018 00:36:43 +0100627202937Spark-based improved Basin-Hopping Monte Carlo algorithm for structural optimization of alloy clusters
https://medworm.com/627202936/spark-based-improved-basin-hopping-monte-carlo-algorithm-for-structural-optimization-of-alloy-cluste/
Publication date: Available online 16 November 2018Source: Physics Letters AAuthor(s): Yuan-Hua Yang, Jun-Fa Zhang, Jin-Bo Wang, Xian-Bin Xu, Gui-Fang Shao, Yu-Hua WenAbstractCoPt alloy clusters are promising candidates for catalysts in fuel-cell applications because of their enhanced catalytic performances compared with pure Pt clusters. In this article, an improved Basin-Hopping Monte Carlo (BHMC) algorithm is proposed to optimize the stable structures of CoPt clusters with different sizes and compositions, and the Spark parallel framework is employed to accelerate the structural optimizations. The results show that the improved BHMC algorithm has higher probability to find the lowest-energy structure and more rapid convergence than the traditional BHMC one. Through the comparison of dif...Physics Letters AjournalsSun, 18 Nov 2018 00:36:43 +0100627202936Hierarchical centralities of information transmissions in reaching a consensus
https://medworm.com/626573364/hierarchical-centralities-of-information-transmissions-in-reaching-a-consensus/
Publication date: Available online 15 November 2018Source: Physics Letters AAuthor(s): Hong-Yuan Xu, Yu-Pin Luo, Jinn-Wen Wu, Ming-Chang HuangAbstractThe question, how central indications arise from an undirected environment and lead to collective behaviors, is analyzed based on a simple model of opinion dynamics, called the DeGroot model. We first reformulate the necessary and sufficient condition for reaching a consensus, then the condition is used to set up the pattern of information transmissions. By classifying the individuals into a sequential series of classes and by giving the dynamic contents of centrality, we demonstrate that the hierarchical centralities with descend strength are associated with the sequential series of classes in information transmissions. The results provide w...Physics Letters AjournalsFri, 16 Nov 2018 20:12:30 +0100626573364Periodic solutions for discrete-time Cohen–Grossberg neural networks with delays
https://medworm.com/626573363/periodic-solutions-for-discrete-time-cohengrossberg-neural-networks-with-delays/
Publication date: Available online 15 November 2018Source: Physics Letters AAuthor(s): Shang Gao, Rong Shen, Tianrui ChenAbstractIn this paper, the existence of periodic solutions for general discrete-time Cohen–Grossberg neural networks with delays (DCGNND) is investigated. Based on graph theory, coincidence degree theory, and Lyapunov method, a sufficient criterion ensuring the existence of periodic solutions for DCGNND is established. In the end, an example and its numerical simulation are given to demonstrate the effectiveness of the theoretical result. (Source: Physics Letters A)Physics Letters AjournalsFri, 16 Nov 2018 20:12:30 +0100626573363Measurement of bunch length evolution in electron beam macropulse of S-band linac using coherent edge radiation
https://medworm.com/626573362/measurement-of-bunch-length-evolution-in-electron-beam-macropulse-of-s-band-linac-using-coherent-edg/
Publication date: Available online 15 November 2018Source: Physics Letters AAuthor(s): Norihiro Sei, Heishun Zen, Hideaki OhgakiAbstractIntense coherent edge radiation (CER) with a power of 0.10 mW was observed in a straight line with an undulator of Kyoto University Free Electron Laser (KU-FEL). To investigate the evolution of a bunch length in a macropulse of an electron beam, a technique was developed using the CER beam. The measured air-extracted CER beam profile has a hollow structure resembling the first-order Laguerre-Gaussian mode with asymmetric intensity in horizontal direction. It roughly agrees with the profile calculated considering the effective area of a deflection mirror employed to extract the beam from the FEL optical cavity into air. The root-mean-squared (RMS) bunch len...Physics Letters AjournalsFri, 16 Nov 2018 20:12:30 +0100626573362Some super systems with local bi-Hamiltonian operators
https://medworm.com/626573361/some-super-systems-with-local-bi-hamiltonian-operators/
Publication date: Available online 15 November 2018Source: Physics Letters AAuthor(s): Binfang Gao, Kai Tian, Q.P. LiuAbstractFor a class of super skew-symmetric operators with eight parameters, two kinds of super Hamiltonian operators are identified by the method of functional multi-vectors. Appropriate decompositions of these operators lead to compatible super Hamiltonian pairs which in turn produce nonlinear super bi-Hamiltonian systems from the trivial x-translation flow. As examples, besides the super Korteweg–de Vries equations and other known ones, new super generalizations are obtained for the Riemann equation, the Hunter–Saxton equation and the Camassa–Holm equation, all of them admit two compatible local super Hamiltonian operators. (Source: Physics Letters A)Physics Letters AjournalsFri, 16 Nov 2018 20:12:30 +0100626573361Dynamics of conservative peakons in a system of Popowicz
https://medworm.com/626573360/dynamics-of-conservative-peakons-in-a-system-of-popowicz/
We present the explicit solution for the two-peakon dynamics, and describe some of the novel features of the interaction of peakons in the Popowicz system. (Source: Physics Letters A)Physics Letters AjournalsFri, 16 Nov 2018 20:12:30 +0100626573360Research on bandgap property of a novel small size multi-band phononic crystal
https://medworm.com/625319739/research-on-bandgap-property-of-a-novel-small-size-multi-band-phononic-crystal/
Publication date: Available online 12 November 2018Source: Physics Letters AAuthor(s): Yake Dong, Hong Yao, Jun Du, Jingbo Zhao, Chao DingAbstractA novel small size multi-band gaps phononic crystal (hPC) composed of the periodic plumbum and aluminum mass has been investigated in this paper, we calculated the dispersion relations and the displacement fields with finite element method (FEM). The influences of the geometrical parameters and materials parameters on the band structure are further investigated. We studied the influence factors of band gap by the model of origin anti-resonance. There are many flat bands in the characteristic frequency curve. The band gap covers a large range in low frequency. (Source: Physics Letters A)Physics Letters AjournalsWed, 14 Nov 2018 11:12:34 +0100625319739Monodromy in non-integrable systems on certain compact classical phase spaces
https://medworm.com/625319738/monodromy-in-non-integrable-systems-on-certain-compact-classical-phase-spaces/
Publication date: Available online 12 November 2018Source: Physics Letters AAuthor(s): Dmitrií A. Sadovskií, Boris I. ZhilinskiíAbstractOn the example of bending vibrational polyads of the acetylene molecule (C2H2) in the approximation of the 1:1:1:1 resonant oscillator with axial symmetry, whose geometry is similar to the n-shell approximation of the perturbed hydrogen atom, we show how remaining invariant tori of the underlying classical non-integrable system form a nontrivial continuous family with monodromy. We read this monodromy off the quantum energy spectrum which was observed experimentally by spectroscopists, and we uncover its origins through the particular topology, geometry, and symmetry. We explain how monodromy characterizes the chaotic region surrounded by the tori. We d...Physics Letters AjournalsWed, 14 Nov 2018 11:12:34 +0100625319738Spontaneous breaking of one-dimensional chains investigated with scanning tunneling microscopy
https://medworm.com/625319737/spontaneous-breaking-of-one-dimensional-chains-investigated-with-scanning-tunneling-microscopy/
Publication date: Available online 12 November 2018Source: Physics Letters AAuthor(s): Xueying ZhaoAbstractLandau (1937) [1] had an argument that one-dimensional long chains are not stable at finite temperature, and will break into short sections due to thermal fluctuation. However, until recently, fragmentation of one-dimensional chains by formation of thermal vacancies was first discovered in Bagatskii et al. (2014) [6] for the Xenon that physically adsorbed in the grooves of single-walled carbon nanotube bundles. In this work, scanning tunneling microscopy (STM) was first used to observe the influence of thermal fluctuations on the length of one-dimensional chains of the amino acids systems chemically adsorbed on metal surfaces. One-dimensional chains of amino acids formed on noble meta...Physics Letters AjournalsWed, 14 Nov 2018 11:12:34 +0100625319737Interaction of solitons with impurities in anisotropic ferromagnetic chains
https://medworm.com/625319736/interaction-of-solitons-with-impurities-in-anisotropic-ferromagnetic-chains/
Publication date: Available online 13 November 2018Source: Physics Letters AAuthor(s): R.S. Kamburova, S.K. Varbev, M.T. PrimatarowaAbstractThe interaction of bright solitons with impurities in the on-site anisotropy of a ferromagnetic chain is studied. This type of impurities leads to linear and nonlinear perturbing terms in the corresponding nonlinear Schrödinger equation. We have found static soliton-impurity bound states and considered the conditions for their formation. For large values of the anisotropy the character of the impurities is mainly linear. The interaction of propagating solitons with the impurities is also investigated. We have obtained that the solitons can be transmitted, trapped or reflected. The behavior depends on the soliton velocity and width, magnetic parameters...Physics Letters AjournalsWed, 14 Nov 2018 11:12:34 +0100625319736Editors
https://medworm.com/625319719/editors/
Publication date: 12 January 2019Source: Physics Letters A, Volume 383, Issues 2–3Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 14 Nov 2018 11:12:34 +0100625319719Directed Percolation Phase Transition at the Onset of STI in an Inhomogeneous Coupled Map Lattice
https://medworm.com/623853406/directed-percolation-phase-transition-at-the-onset-of-sti-in-an-inhomogeneous-coupled-map-lattice/
Publication date: Available online 9 November 2018Source: Physics Letters AAuthor(s): Sujay Biswas, Alaka DasAbstractA model for inhomogeneously coupled logistic maps is considered to find some critical exponents in the transition from inhomogeneous steady state to spatiotemporal chaos through spatiotemporal intermittency. The laminar state in the model is described by inhomogeneous steady state with spatial period two. We obtain a complete set of static exponents which match with the corresponding directed percolation(DP) values in (1+1) dimension. We also find four nonuniversal spreading exponents in which three exponents are in agreement with DP values. The model in which absorbing state is inhomogeneous steady state, contributes a new example in evidence of Pomeau's [18] conjecture tha...Physics Letters AjournalsSun, 11 Nov 2018 16:19:03 +0100623853406Formation of a small ‘bead lightning’ in a half-microsecond discharge in air
https://medworm.com/622375140/formation-of-a-small-bead-lightning-in-a-half-microsecond-discharge-in-air/
Publication date: Available online 7 November 2018Source: Physics Letters AAuthor(s): D.V. Beloplotov, V.F. TarasenkoAbstractThe formation of periodic plasma clots which form a discharge channel similar to bead lightning has been studied with a four-channel intensified charge-coupled device (ICCD) camera simultaneously with the recording of voltage and current waveforms. It was found that a diffuse discharge was formed at the initial stage due to the development of a wide streamer. Runaway electrons were registered. Beads were formed as a result of the development of the spark leader after the diffuse stage. It was assumed that the diameter of the spark leader periodically changes in accordance with the change in the electric field strength in the spark leader head. As a result, narrow sec...Physics Letters AjournalsThu, 08 Nov 2018 21:12:39 +0100622375140Comment on ‘Deterministic CNOT gate and entanglement swapping for photonic qubits using a quantum-dot spin in a double-sided optical microcavity’ by H.F. Wang et al., Physics Letters A 377, 2870–2876 (2013)
https://medworm.com/622375139/comment-on-deterministic-cnot-gate-and-entanglement-swapping-for-photonic-qubits-using-a-quantum-/
Publication date: Available online 7 November 2018Source: Physics Letters AAuthor(s): Amor Gueddana, Vasudevan Lakshminarayanan (Source: Physics Letters A)Physics Letters AjournalsThu, 08 Nov 2018 21:12:39 +0100622375139Comparing mechanical analysis with generalized-competitive-mode analysis for the plasma chaotic system
https://medworm.com/622375138/comparing-mechanical-analysis-with-generalized-competitive-mode-analysis-for-the-plasma-chaotic-syst/
Publication date: Available online 7 November 2018Source: Physics Letters AAuthor(s): Yingjuan Yang, Guoyuan QiAbstractThe plasma chaotic system is a dissipative dynamical system modeled by a parametric plasma instability arising from the interaction of the whistler and ion acoustic waves with the plasma oscillation near the lower hybrid resonance. The amplitudes of these three oscillations obey a three-dimensional system of ordinary differential equations that exhibits chaos for certain parameter values. Besides the maximal Lyapunov exponent technique, a generalized-competitive-mode (GCM) technique has been proposed to evaluate parameter values associated with chaos. A mechanical analysis has also been proposed to reveal the mechanisms underlying the different dynamical modes including ch...Physics Letters AjournalsThu, 08 Nov 2018 21:12:39 +0100622375138On the effect of fractional statistics on quantum ion acoustic waves
https://medworm.com/621741750/on-the-effect-of-fractional-statistics-on-quantum-ion-acoustic-waves/
Publication date: Available online 6 November 2018Source: Physics Letters AAuthor(s): Kamel OurabahAbstractIn this paper, I study the effect of a small deviation from the Fermi–Dirac statistics on the quantum ion acoustic waves. For this purpose, a quantum hydrodynamic model is developed based on the Polychronakos statistics, which allows for a smooth interpolation between the Fermi and Bose limits, passing through the case of classical particles. The model includes the effect of pressure as well as quantum diffraction effects through the Bohm potential. The equation of state for electrons obeying fractional statistics is obtained and the effect of fractional statistics on the kinetic energy and the coupling parameter is analyzed. Through the model, the effect of fractional statistics on...Physics Letters AjournalsWed, 07 Nov 2018 16:09:37 +0100621741750On the dynamics of the Szekeres system
https://medworm.com/621741749/on-the-dynamics-of-the-szekeres-system/
We describe the dynamics of the Szekeres system when one of these two rational first integrals is negative, showing that all the orbits come from the infinity of R4 and go to infinity. (Source: Physics Letters A)Physics Letters AjournalsWed, 07 Nov 2018 16:09:37 +0100621741749Electric double layer of electrons: Attraction between two like-charged surfaces induced by Fermi–Dirac statistics
https://medworm.com/621741748/electric-double-layer-of-electrons-attraction-between-two-like-charged-surfaces-induced-by-fermi/
Publication date: Available online 6 November 2018Source: Physics Letters AAuthor(s): Mitja Drab, Veronika Kralj-IgličAbstractRecently we reported that Fermi–Dirac statistics of electrons contained between two oppositely charged surfaces separated by the order of nanometers create overlapping electric double layers with repulsive total force between the surfaces. Here, we present a new branch of solutions to the same variational problem resulting in higher energy densities and identify regions of the phase space where the force between two like-charged surfaces is attractive. (Source: Physics Letters A)Physics Letters AjournalsWed, 07 Nov 2018 16:09:37 +0100621741748Efficient scheme for passive decoy-state reference-frame-independent quantum key distribution
https://medworm.com/621112785/efficient-scheme-for-passive-decoy-state-reference-frame-independent-quantum-key-distribution/
Publication date: Available online 5 November 2018Source: Physics Letters AAuthor(s): Jian-Rong Zhu, Chun-Mei Zhang, Qin WangAbstractReference-frame-independent quantum key distribution (RFI-QKD) has been demonstrated to be reliable and useful both in theories and experiments, which is intrinsically robust against slowly varying reference frames. In this paper, we propose an efficient scheme of passive decoy-state RFI-QKD based on the parametric down-conversion source, where a beam splitter splits the idler pulses into four local detection events to improve the performance of RFI-QKD systems. In addition, we demonstrate the worst relative rotation of reference frames in our scheme. Simulation results show that our scheme can achieve good performance even at the worst-case scenario. (Source...Physics Letters AjournalsTue, 06 Nov 2018 11:30:33 +0100621112785True spin and pseudo spin entanglement around Dirac Points in graphene with Rashba spin–orbit interaction
https://medworm.com/621112784/true-spin-and-pseudo-spin-entanglement-around-dirac-points-in-graphene-with-rashba-spinorbit-inte/
Publication date: Available online 5 November 2018Source: Physics Letters AAuthor(s): Zheng Liu, Chao Zhang, J.C. CaoAbstractWe analytically obtained the Schmidt decomposition of the entangled state between the pseudo spin and the true spin in graphene with Rashba spin–orbit coupling. The entangled state has the standard form of the Bell state, where the SU(2) spin symmetry is broken. These states can be explicitly expressed as the superposition of two nonorthogonal, but mirror symmetrical spin states entangled with the pseudo spin states. Because of the closely locking between the pseudo spin and the true spin, it is found that the orbit curve in the spin-polarization parameter space for the fixed equi-energy contour around Dirac points has the same shape as the δk→-contour. Due to t...Physics Letters AjournalsTue, 06 Nov 2018 11:30:33 +0100621112784Improving direct state measurements by using rebits in real enlarged Hilbert spaces
https://medworm.com/621112783/improving-direct-state-measurements-by-using-rebits-in-real-enlarged-hilbert-spaces/
Publication date: Available online 5 November 2018Source: Physics Letters AAuthor(s): Le Bin HoAbstractWe propose a protocol to improve the accuracy of direct complex state measurements (DSM) by using rebits in real Hilbert spaces. We show that to improve the accuracy, the initial complex state should be decomposed into the real and imaginary parts and stored in an extended state (rebit) which can be tracked individually by two bases of an extra qubit. For pure states, the numerical calculations show that the trace distances between the true state and the reconstructed state obtained from the rebit method are more precise than those ones obtained from the usual DSM and quantum state tomography (SQT) because the number of projective measurements is reduced. For mixed states, the rebit metho...Physics Letters AjournalsTue, 06 Nov 2018 11:30:33 +0100621112783Effect of non-metallic X(X=F, N, S) and Cr co-doping on properties of BiFeO3: A first-principles study
https://medworm.com/619005372/effect-of-non-metallic-xxf-n-s-and-cr-co-doping-on-properties-of-bifeo3-a-first-principles-stu/
In this study, the structural, magnetic, electric and optical properties in X (X=F, N, S) and Cr co-doped BiFeO3 (BFO) are calculated using the density functional theory. For Cr–X co-doping case, the structure of BFO undergo a phase transition from monoclinic to triclinic structure accompanying net magnetic moments of 5.92 μB, 6.04 μB and 7.80 μB, for Cr–F co-doping, Cr–N co-doping and Cr–S co-doping, respectively. The underlying physical mechanisms are the lattice distortions tunned by doping. The decreased Fe–O–Fe bond angles and Fe–O bond lengths will bring weak antiferromagnetism superexchange interaction. In addition, the band gaps of Cr–X co-doping cases are decreased from 2.20 eV (BFO bulk) to 1.31 eV and 1.80 eV for Cr–F co-doping and Cr–S co-doping, respecti...Physics Letters AjournalsFri, 02 Nov 2018 12:12:29 +0100619005372Impact of non-uniform heat sink/source and convective condition in radiative heat transfer to Oldroyd-B nanofluid: A revised proposed relation
https://medworm.com/618581592/impact-of-non-uniform-heat-sinksource-and-convective-condition-in-radiative-heat-transfer-to-oldroy/
Publication date: Available online 31 October 2018Source: Physics Letters AAuthor(s): M. Irfan, M. Khan, W.A. KhanAbstractNanofluids are embryonic as auspicious thermo liquids for application of heat transfer which have been scrutinized precisely, in current eons. Thermo-physical properties of these liquids have noteworthy stimulus on their heat transfer features. The manifestation of dense nanoparticles in the base liquid ominously intensifies the effective liquid thermal conductivity and therefore heightens the features of heat transfer. The highest attention of this exertion is to investigate the features of nanoparticles mass flux conditions and non-uniform heat sink/source on magnetite Oldroyd-B nanofluid. Additionally, heat convective and thermal radiation mechanisms are considered. ...Physics Letters AjournalsThu, 01 Nov 2018 17:12:36 +0100618581592Hjelmslev quadrilateral central configurations
https://medworm.com/618154498/hjelmslev-quadrilateral-central-configurations/
Publication date: Available online 30 October 2018Source: Physics Letters AAuthor(s): M. Alvarez-Ramírez, J. LlibreAbstractA Hjelmslev quadrilateral is a quadrilateral with two right angles at opposite vertices. Using mutual distances as coordinates, we show that any four-body central configuration forming a Hjelmslev quadrilateral must be a right kite configuration. (Source: Physics Letters A)Physics Letters AjournalsWed, 31 Oct 2018 22:12:29 +0100618154498Quasi-exactly solvable quantum systems with explicitly time-dependent Hamiltonians
https://medworm.com/618154497/quasi-exactly-solvable-quantum-systems-with-explicitly-time-dependent-hamiltonians/
Publication date: Available online 30 October 2018Source: Physics Letters AAuthor(s): Andreas Fring, Thomas FrithAbstractFor a large class of time-dependent non-Hermitian Hamiltonians expressed in terms linear and bilinear combinations of the generators for an Euclidean Lie-algebra respecting different types of PT-symmetries, we find explicit solutions to the time-dependent Dyson equation. A specific Hermitian model with explicit time-dependence is analyzed further and shown to be quasi-exactly solvable. Technically we constructed the Lewis–Riesenfeld invariants making use of the metric picture, which is an equivalent alternative to the Schrödinger, Heisenberg and interaction picture containing the time-dependence in the metric operator that relates the time-dependent Hermitian Hamilton...Physics Letters AjournalsWed, 31 Oct 2018 22:12:29 +0100618154497Solitary waves in a long structure of charged particles confined in the linear Paul trap
https://medworm.com/618154496/solitary-waves-in-a-long-structure-of-charged-particles-confined-in-the-linear-paul-trap/
Publication date: Available online 31 October 2018Source: Physics Letters AAuthor(s): R. Syrovatka, Yu. Medvedev, V. Filinov, L. Vasilyak, L. Deputatova, V. Vladimirov, V. PecherkinAbstractThis paper demonstrates the possibility of generation of density waves in the form of individual humps in a long structure of the one-component Coulomb system of dust particles confined in the linear Paul traps in air under normal conditions Our numerical simulations by particle-in-cell method support this possibility. Physical possibilty of analogous the hump density waves (caustics) is discussed by V. I. Arnold in his book ‘Catastrophe Theory’ and is caused by the nonuniform velocity distribution of dust particles. (Source: Physics Letters A)Physics Letters AjournalsWed, 31 Oct 2018 22:12:29 +0100618154496New findings for two new type sine hyperbolic potentials
https://medworm.com/617511716/new-findings-for-two-new-type-sine-hyperbolic-potentials/
Publication date: Available online 29 October 2018Source: Physics Letters AAuthor(s): Qian Dong, Guo-Hua Sun, Jian Jing, Shi-Hai DongAbstractWe propose two new type sine hyperbolic potentials V(x)=a2sinh2(x)−ktanh2(x) and V(x)=c2sinh4(x)−ktanh2(x). They may become single- or double-well potentials depending on the potential parameters a,c and k. We find that its exact solutions can be written as the confluent Heun functions Hc(α,β,γ,δ,η;z), in which the energy level E is involved inside the parameter η. The properties of the wave functions, which is strongly relevant for the potential parameters a,c and k, are illustrated. (Source: Physics Letters A)Physics Letters AjournalsTue, 30 Oct 2018 17:30:32 +0100617511716Simulating pedestrian flow through narrow exits
https://medworm.com/617511715/simulating-pedestrian-flow-through-narrow-exits/
Publication date: Available online 29 October 2018Source: Physics Letters AAuthor(s): Milad Haghani, Majid SarviAbstractIntroduction: The flow of pedestrians through narrow doorways is one of the most common features of crowd motions and evacuations. It is particularly an important aspect of pedestrian simulations models since their accuracy depends highly on their ability to produce realistic exit flow rates. The problem has been extensively studied in the literature, but many aspects of it have remained controversial with mixed (and often contradictory) evidence emerging from different studies and different methods.Methods: We discuss the significance of parameter calibration for accurate simulation of pedestrian flow through narrow exits using social force model. Based on sensitivity an...Physics Letters AjournalsTue, 30 Oct 2018 17:30:32 +0100617511715Tunable rectification and negative differential resistance induced by asymmetric doping in phosphorene nanoribbon
https://medworm.com/617511714/tunable-rectification-and-negative-differential-resistance-induced-by-asymmetric-doping-in-phosphore/
Publication date: Available online 29 October 2018Source: Physics Letters AAuthor(s): Somayeh FotoohiAbstractBy using first-principles calculations based on density functional theory and non-equilibrium Green's function, we present the electronic transport properties of two kinds of devices based on armchair phosphorene nanoribbons, namely, A device, and B device. In A device, the phosphorus atoms in the center of armchair phosphorene nanoribbon have been replaced by impurity atoms of the S and Si, whereas in the B device, the impurity atoms are at the edge of ribbon. The results show that the current–voltage characteristics for both devices have striking nonlinear features and the rectifying behaviors strongly depend on the positions of impurity atoms. The highest rectification ratio is...Physics Letters AjournalsTue, 30 Oct 2018 17:30:32 +0100617511714Modular-value-based metrology with spin coherent pointers
https://medworm.com/617511713/modular-value-based-metrology-with-spin-coherent-pointers/
Publication date: Available online 29 October 2018Source: Physics Letters AAuthor(s): Le Bin Ho, Yasushi KondoAbstractWe discuss an optimal modular-value-based measurement with a spin coherent pointer: A quantum system is exposed to a field whose strength is to be estimated through its modular value. We evaluate the quantum Fisher information as a figure of merit. We found that the modular-value-based measurement can reach the same ultimate precision limit of the estimation as those of measurements without postselections. The quantum Fisher information can be increased when the dimension of the pointer state increases. We also consider the pointer under a phase-flip error. Our study should motivate researchers to apply the modular-value-based measurements for quantum metrology. (Source: Ph...Physics Letters AjournalsTue, 30 Oct 2018 17:30:32 +0100617511713Editors
https://medworm.com/617511701/editors/
Publication date: 5 January 2019Source: Physics Letters A, Volume 383, Issue 1Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 30 Oct 2018 17:30:32 +0100617511701Thermalization of electron–positron plasma with quantum degeneracy
https://medworm.com/615806950/thermalization-of-electronpositron-plasma-with-quantum-degeneracy/
Publication date: Available online 25 October 2018Source: Physics Letters AAuthor(s): M.A. Prakapenia, I.A. Siutsou, G.V. VereshchaginAbstractThe non-equilibrium electron–positron–photon plasma thermalization process is studied using relativistic Boltzmann solver, taking into account quantum corrections both in non-relativistic and relativistic cases. Collision integrals are computed from exact QED matrix elements for all binary and triple interactions in the plasma. It is shown that in non-relativistic case (temperatures kBT≤0.3mec2) binary interaction rates dominate over triple ones, resulting in establishment of the kinetic equilibrium prior to final relaxation towards the thermal equilibrium, in agreement with the previous studies. On the contrary, in relativistic case (final tem...Physics Letters AjournalsSat, 27 Oct 2018 12:24:37 +0100615806950Exploration the p-type doping mechanism of GaAs nanowires from first-principles study
https://medworm.com/615806944/exploration-the-p-type-doping-mechanism-of-gaas-nanowires-from-first-principles-study/
Publication date: Available online 26 October 2018Source: Physics Letters AAuthor(s): Yu Diao, Lei Liu, Sihao XiaAbstractUsing first-principle calculations, we present a systematic investigation upon the influence of p-type doping on the structural and electronic properties of H-passivated GaAs nanowires with wurtzite structure. The GaAs nanowire models of different doping types, different doping elements, different doping positions and different doping concentrations are established. The calculated formation energies show that Zn element becomes more competitive or even slightly favored in realizing p-type doping compared to Be element. For an individual Zn incorporation model, Zn atom tends to substitute the subsurface Ga atom. As increasing Zn doping concentration, the p-type doping pro...Physics Letters AjournalsSat, 27 Oct 2018 12:24:37 +0100615806944Effects of mass transfer on MHD second grade fluid towards stretching cylinder: A novel perspective of Cattaneo-Christov heat flux model
https://medworm.com/615806943/effects-of-mass-transfer-on-mhd-second-grade-fluid-towards-stretching-cylinder-a-novel-perspective-/
This study can be used an application of central heating system and to measure the fast chemical reactions rates. (Source: Physics Letters A)Physics Letters AjournalsSat, 27 Oct 2018 12:24:37 +0100615806943Ab initio and Monte Carlo studies of phase transitions and magnetic properties of YCrO3: Heisenberg model
https://medworm.com/615806942/ab-initio-and-monte-carlo-studies-of-phase-transitions-and-magnetic-properties-of-ycro3-heisenberg-/
Publication date: Available online 26 October 2018Source: Physics Letters AAuthor(s): S. Sidi Ahmed, G. Dimitri Ngantso, M. Boujnah, A. Benyoussef, A. El KenzAbstractBy using the density functional theory (DFT) and Monte Carlo simulations (MCS) with the Heisenberg model, we have studied magnetic properties of the bulk perovskite YCrO3. The exchange couplings of the Heisenberg model and the magnetic anisotropy are investigated. The 110 direction in the crystalline structure of the compound has shown the minimum energy, it is the easy magnetic direction. Using Monte Carlo simulations, the magnetizations behavior, the effects of system parameters and the critical exponents of the compound YCrO3 are implemented. It is shown that the bulk perovskite YCrO3 belongs to the 3D Heisenberg universali...Physics Letters AjournalsSat, 27 Oct 2018 12:24:37 +0100615806942Picturing quantum phase transitions
https://medworm.com/615806941/picturing-quantum-phase-transitions/
Publication date: Available online 26 October 2018Source: Physics Letters AAuthor(s): C. Muñoz, M. Gaeta, R. Gomez, A.B. KlimovAbstractWe discuss the quantum phase transitions (QPT) in N-spin chains from the point of view of collective observables. We show that the measurement space representation is a convenient tool for the analysis of phase transitions, allowing the determination of an appropriate set of macroscopic order parameters (for a given Hamiltonian). Quantum correlations in the vicinity of the critical points are analyzed both in the ground states and low temperature thermal states. (Source: Physics Letters A)Physics Letters AjournalsSat, 27 Oct 2018 12:24:37 +0100615806941Crossover effects and finite-size scaling on the temperature dependence of paraconductivity in YBa2Cu3O6.9 and Bi2Sr2CaCu30x compounds
https://medworm.com/615377353/crossover-effects-and-finite-size-scaling-on-the-temperature-dependence-of-paraconductivity-in-yba2c/
Publication date: Available online 25 October 2018Source: Physics Letters AAuthor(s): A.V. Wirngo, R.M. Keumo Tsiaze, S.C. Kenfack, E. BaloïtchaAbstractAn investigation into the superconducting order parameter thermodynamic fluctuations and their manifestations on paraconductivity in cuprate superconductors is done using a renormalized Gaussian approach based on the Ginzburg–Landau theory. The temperature dependence of paraconductivity is affected by repulsive interactions between Cooper pairs and does not follow the universal power laws predicted by the conventional Aslamazov–Larkin theory. In addition to the well known Lawrence–Doniach crossover from three to two dimensions, we also highlight the crossover from one-dimensional to two-dimensional behavior and the crossover from wea...Physics Letters AjournalsFri, 26 Oct 2018 17:24:31 +0100615377353Thermalization of electron-positron plasma with quantum degeneracy
https://medworm.com/615377352/thermalization-of-electron-positron-plasma-with-quantum-degeneracy/
Publication date: Available online 25 October 2018Source: Physics Letters AAuthor(s): M.A. Prakapenia, I.A. Siutsou, G.V. VereshchaginAbstractThe non-equilibrium electron-positron-photon plasma thermalization process is studied using relativistic Boltzmann solver, taking into account quantum corrections both in non-relativistic and relativistic cases. Collision integrals are computed from exact QED matrix elements for all binary and triple interactions in the plasma. It is shown that in non-relativistic case (temperatures kBT≤0.3mec2) binary interaction rates dominate over triple ones, resulting in establishment of the kinetic equilibrium prior to final relaxation towards the thermal equilibrium, in agreement with the previous studies. On the contrary, in relativistic case (final tempera...Physics Letters AjournalsFri, 26 Oct 2018 17:24:31 +0100615377352Effects of carbon doping and vacancy defect on the magnetism of anatase TiO2
https://medworm.com/615377351/effects-of-carbon-doping-and-vacancy-defect-on-the-magnetism-of-anatase-tio2/
In this study, the effects of C doping and vacancy defect on the magnetism of TiO2 were investigated by generalized gradient approximation and Hubbard U method based on density functional theory. Systems with coexisting interstitial C and O vacancies achieved half-metallic ferromagnetism, and the Curie temperature was above the room temperature. The system used as electron injection source reached 100% electron spin polarization. The Ti32CO2O62c system exhibited ferromagnetism, and the Curie temperature was above the room temperature. The magnetism source of Ti16CiOa31 and Ti32CO2Oc62 demonstrated strong hybrid coupling electron exchange effects among Ti-3d, O-2p, and C-2porbits which is consistent with the RKKY model of d-p orbital electron exchange. (Source: Physics Letters A)Physics Letters AjournalsFri, 26 Oct 2018 17:24:31 +0100615377351High thermoelectric performance of one graphene nanoribbon with line defects
https://medworm.com/615377350/high-thermoelectric-performance-of-one-graphene-nanoribbon-with-line-defects/
Publication date: Available online 25 October 2018Source: Physics Letters AAuthor(s): Wen-Lai Mu, Hai-Na Wu, Yu Han, Wei-Jiang GongAbstractWe investigate the quantum transport through zigzag graphene nanoribbons with embedded “5-7-5”-edge line defects, by means of the non-equilibrium Green's function technique. It is found that when two semi-infinite line defects exist in the nanoribbon, notable Fano antiresonance takes place in the quantum transport process, which enables to drive the apparent thermoelectric effect. We propose this structure to be a promising candidate for improving the thermoelectric efficiency based on graphene nanoribbons. (Source: Physics Letters A)Physics Letters AjournalsFri, 26 Oct 2018 17:24:31 +0100615377350Tunneling-induced ultraslow solitons in triangular quantum dot molecules
https://medworm.com/615377349/tunneling-induced-ultraslow-solitons-in-triangular-quantum-dot-molecules/
Publication date: Available online 25 October 2018Source: Physics Letters AAuthor(s): Dong Sun, Hongjun Zhang, Hui Sun, Xiaowei Li, Gaiying WangAbstractWe theoretically investigate the propagation of a weak probe laser pulse in a triangular quantum dot molecules scheme based on the tunneling induced transparency. We find that the ultraslow optical solitons can be realized due to the destructive quantum interference induced by the interdot tunneling coupling which can be adjusted by the gate voltage appropriately. This work may provide practical applications such as electro-optic modulated devices and other information processes in semiconductor quantum dots structure. (Source: Physics Letters A)Physics Letters AjournalsFri, 26 Oct 2018 17:24:31 +0100615377349Dynamics of Bose–Einstein condensate in driven tilted optical lattices
https://medworm.com/615377347/dynamics-of-boseeinstein-condensate-in-driven-tilted-optical-lattices/
Publication date: Available online 25 October 2018Source: Physics Letters AAuthor(s): Ai-Xia Zhang, Li-Xia Cai, Zi-Fa Yu, Na-Na Chang, Si-Qi He, Ju-Kui XueAbstractWe study the dynamics of Bose–Einstein condensate in one-dimensional driven tilted periodic optical lattices by using variational approximation and numerical simulation. Rich phenomena are revealed, including diffusion, self-trapping, breather and soliton, which strongly depend on the atomic interaction, the amplitude of the modulation, the constant force and the phase difference between the Bloch oscillations and the drive. The critical conditions for the dynamical transition from diffusion to self-trapping and for the formation of the soliton are derived analytically. In addition, the phase diagrams of dynamical transitions a...Physics Letters AjournalsFri, 26 Oct 2018 17:24:31 +0100615377347Quantum criticality of quantum speed limit for a two-qubit system in the spin chain with the Dzyaloshinsky-Moriya interaction
https://medworm.com/614949462/quantum-criticality-of-quantum-speed-limit-for-a-two-qubit-system-in-the-spin-chain-with-the-dzyalos/
Publication date: Available online 25 October 2018Source: Physics Letters AAuthor(s): Shaoying Yin, Jie Song, Shutian LiuAbstractWe study the quantum speed limit (QSL) time of a two-qubit system coupled to a spin-chain model with the Dzyaloshinsky-Moriya (DM) interaction. For the Bell state coupled to the Ising model or anisotropic XY model, we find that there is a prominent corresponding relationship between the QSL time and quantum phase transition in a spin-chain environment with larger scale, and the DM interaction can strongly enhance or suppress the response relation. Remarkably, when the surrounding environment is set to the XX model, the DM interaction makes it possible for us to witness the quantum phase transition by the local anomalous enhancement of the QSL time near the critic...Physics Letters AjournalsThu, 25 Oct 2018 22:30:36 +0100614949462Analytical prediction of multiple solutions for MHD Jeffery–Hamel flow and heat transfer utilizing KKL nanofluid model
https://medworm.com/614314094/analytical-prediction-of-multiple-solutions-for-mhd-jefferyhamel-flow-and-heat-transfer-utilizing/
Publication date: Available online 23 October 2018Source: Physics Letters AAuthor(s): Puneet Rana, Nisha Shukla, Yogesh Gupta, Ioan PopAbstractIn this framework, the novel analytical approach is presented to predict the dual solutions of Jeffery–Hamel (JH) transport model utilizing KKL (Koo–Kleinstreuer–Li) Al2O3 model with magnetic field, Ohmic heating and viscous dissipation. The predictor homotopy analysis method (PHAM) is applied to realize the existence of multiple solutions (bifurcation) for stretching/shrinking parameter and channel angle. It is observed that the dual solutions exist only for convergent channel. The eigenvalue problem is constructed to perform stability analysis which shows the physically stability of the upper branch. A numerical validation with Runge–Kutta...Physics Letters AjournalsWed, 24 Oct 2018 18:24:36 +0100614314094Wada boundary bifurcations induced by boundary saddle–saddle collision
https://medworm.com/614314093/wada-boundary-bifurcations-induced-by-boundary-saddlesaddle-collision/
Publication date: Available online 23 October 2018Source: Physics Letters AAuthor(s): Xiao-Ming Liu, Jun Jiang, Ling Hong, Dafeng TangAbstractIn this letter, a Wada boundary bifurcation (WBB) induced by a boundary saddle touching another boundary saddle is first found through the study of a forced damped pendulum. The WBB can be quantitatively described by the change both in the number of basins involved and in the geometrical size of the boundary. We perceive the manifold structures of the two saddles, that is, a pre-existence of heteroclinic crossing and the other nearly forming heteroclinic tangency exist before the WBB. So we schematically construct the equivalent topological structure of the manifolds of arbitrary two saddles, and rigorously prove two theorems that indicate the existe...Physics Letters AjournalsWed, 24 Oct 2018 18:24:36 +0100614314093Boson–boson pure-dephasing model with non-Markovian properties
https://medworm.com/614314092/bosonboson-pure-dephasing-model-with-non-markovian-properties/
Publication date: Available online 23 October 2018Source: Physics Letters AAuthor(s): Fei-Lei Xiong, Li Li, Zeng-Bing ChenAbstractIn this paper, we discuss the mechanism of pure-dephasing process with a newly proposed boson–boson model, namely, a bosonic field coupled to another bosonic bath in thermal equilibrium. Our model is fully solvable and can reproduce the pure-dephasing process which is usually described by the well-known spin–boson model, therefore offering a new perspective to understanding decoherence processes in open quantum systems of high dimension. We also show that this model admits a generically non-Markovian dynamics with respect to various different non-Markovian characterizations, i.e., the criteria based on divisibility, quantum regression formula and Wigner func...Physics Letters AjournalsWed, 24 Oct 2018 18:24:36 +0100614314092Morse parameters for the interaction of metals with graphene and silicene
https://medworm.com/614314091/morse-parameters-for-the-interaction-of-metals-with-graphene-and-silicene/
We present Morse parameters for the interaction of graphene and silicene surfaces with the atoms of practically important metals Ni, Ag, and Li. The parameters' values are derived from the dispersion corrected density functional calculations. Two possible cases of sp2-hybridized C/Si atoms in the unbroken graphene/silicene sheets and sp-hybridized atoms near the vacancies are considered. Proposed Morse parameters' sets reproduce binding energies, bond lengths and oscillation frequencies of metal atoms adsorbed on the hollow positions over the rings of C60 and Si60 fullerenes. They also reproduce well the same quantities for the substituted C59M and Si59M fullerenes (M = Ni, Ag, Li). (Source: Physics Letters A)Physics Letters AjournalsWed, 24 Oct 2018 18:24:36 +0100614314091Editors
https://medworm.com/614314078/editors/
Publication date: 5 December 2018Source: Physics Letters A, Volume 382, Issue 48Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 24 Oct 2018 18:24:36 +0100614314078Lump waves, solitary waves and interaction phenomena to the (2 + 1)-dimensional Konopelchenko–Dubrovsky equation
https://medworm.com/613898420/lump-waves-solitary-waves-and-interaction-phenomena-to-the-21-dimensional-konopelchenko/
Publication date: Available online 22 October 2018Source: Physics Letters AAuthor(s): Wenhao Liu, Yufeng Zhang, Dandan ShiAbstractIn this paper, we investigated the (2+1)-dimensional Konopelchenko–Dubrovsky equation. The lump waves, solitary waves as well as interaction between lump waves and solitary waves are presented based on the Hirota bilinear form of this equation. It is worth noting that the rational solutions are obtained by taking a long wave limit, and we also discussed the lump solutions and rogue wave solutions. Moreover, all these solutions are presented via 3-dimensional plots and density plots with choosing some special parameters to show the dynamic graphs. (Source: Physics Letters A)Physics Letters AjournalsTue, 23 Oct 2018 23:18:31 +0100613898420Classical breathers and quantum coherent states in discrete NLS systems
https://medworm.com/613898419/classical-breathers-and-quantum-coherent-states-in-discrete-nls-systems/
We present a comparison of quantum and “semiclassical” trajectories of coherent states that correspond to classical breather solutions of finite discrete nonlinear Schrödinger (DNLS) lattices. The main goal is to explain earlier numerical observations of recurrent return to the vicinity of initial coherent states corresponding to stable breathers that are also spatially localized. This effect can be considered as a quantum manifestation of classical spatial localization. We show that these phenomena are encoded in a simple expression for the distance between the quantum and semiclassical states that involves the basic frequencies of the classical and quantum systems, as well as the breather amplitude and quantum spectral decomposition of the system. A corollary is that recurrence phen...Physics Letters AjournalsTue, 23 Oct 2018 23:18:31 +0100613898419The anisotropic effect of hexagonal warping on the transport
https://medworm.com/613898418/the-anisotropic-effect-of-hexagonal-warping-on-the-transport/
Publication date: Available online 22 October 2018Source: Physics Letters AAuthor(s): Mei-Mei Wu, Zhi-Ming Yu, Hui PanAbstractIn the presence of hexagonal warping (HW), the surface state of a topological insulator (TI) exhibits anisotropic Fermi surface. In this work, we study the transport properties of a TI junction, focusing on the influence of anisotropic effect of the HW on the scattering. We establish general expressions for calculating the scattering with an arbitrary angle between TI surface and the potential step, and find that the transmission probability and conductance have a strong dependence on the angle, making TI junction a promising platform for studying the geometry control of transport. Remarkably, we find that the HW can induce a triple refraction, which gives rise to a...Physics Letters AjournalsTue, 23 Oct 2018 23:18:31 +0100613898418Pseudo topological insulators
https://medworm.com/613898417/pseudo-topological-insulators/
Publication date: Available online 22 October 2018Source: Physics Letters AAuthor(s): C. YuceAbstractWe predict pseudo topological insulators that have been previously overlooked. We determine some conditions under which robust pseudo topological edge states appear and illustrate our idea on the Su–Schrieffer–Heeger (SSH) model with extra chiral symmetry breaking potentials. We discuss that pseudo topological insulating phase transition occurs without band gap closing. (Source: Physics Letters A)Physics Letters AjournalsTue, 23 Oct 2018 23:18:31 +0100613898417Effect of interface structure on deformation behavior of crystalline Cu/amorphous CuZr sandwich structures
https://medworm.com/613898416/effect-of-interface-structure-on-deformation-behavior-of-crystalline-cuamorphous-cuzr-sandwich-stru/
Publication date: Available online 22 October 2018Source: Physics Letters AAuthor(s): H.Y. Song, J.J. Xu, Q. Deng, Y.L. LiAbstractThe effect of interface types (namely, sharp interface and graded interface) and its thickness on the deformation behavior of crystalline/amorphous/crystalline sandwich structures (CACSSs) under tensile loading are studied using molecular dynamics simulation. Compared with the CACSSs with sharp interface, the CACSSs with gradient interface consistently exhibit good plasticity when the interface thickness is larger than 6 nm, due to the coupling effects among crystalline layer, amorphous layer and crystalline–amorphous interface. With the increase of interface thickness, the plastic deformation mechanism of CACSSs with gradient interface changes from the local ...Physics Letters AjournalsTue, 23 Oct 2018 23:18:31 +0100613898416The effect of anti-site disorder and tetragonal distortion on the electronic structure of Ti2VSb
https://medworm.com/613898415/the-effect-of-anti-site-disorder-and-tetragonal-distortion-on-the-electronic-structure-of-ti2vsb/
Publication date: Available online 23 October 2018Source: Physics Letters AAuthor(s): A. Feng, X.Y. ZhangAbstractThe theoretical study published on J. Magn. Magn. Mater. 449 (2018) 515 has predicted that Hg2CuTi-type Ti2VSb is a fully compensated ferrimagnetic semiconductor. In this work, the effect of the anti-site disorder and the tetragonal distortion on the electronic structure of Ti2VSb has been investigated using first-principles calculations. The calculated results indicate that the fully compensated ferrimagnetic semiconductor (FCFS) property of Ti2VSb is sensitive to the tetragonal distortion and FCFS property can be maintained only when the c/a ratio is in the range of 0.95–1.04. When the c/a ratio is not in this range, Ti2VSb is firstly transformed into a fully compensated fer...Physics Letters AjournalsTue, 23 Oct 2018 23:18:31 +0100613898415Exotic vortex structures of the dipolar Bose–Einstein condensates trapped in harmonic-like and toroidal potential
https://medworm.com/612239214/exotic-vortex-structures-of-the-dipolar-boseeinstein-condensates-trapped-in-harmonic-like-and-tor/
Publication date: Available online 18 October 2018Source: Physics Letters AAuthor(s): Rui-Fang Zhang, Xiao-Fei Zhang, Lu LiAbstractBased on the tunable intensity and waist of Gaussian laser, harmonic-like and toroidal potentials can be achieved and the ground-state properties of the dipolar Bose–Einstein condensate (BEC) trapped in such potentials are investigated. It is found that, in the harmonic-like potential, the singly and doubly quantized vortices can exist in the scale condensate and translate respectively into vortex pairs and triangular vortex lattice with increasing dipole–dipole interaction (DDI). Especially, the sandwich-like structure can be observed in the ground-state density profiles by tuning the direction and strength of DDI for some rotating frequency. In the toroid...Physics Letters AjournalsSat, 20 Oct 2018 19:09:32 +0100612239214Massless and quantized modes of kinks in the phase space of superconducting gaps
https://medworm.com/612239213/massless-and-quantized-modes-of-kinks-in-the-phase-space-of-superconducting-gaps/
Publication date: Available online 19 October 2018Source: Physics Letters AAuthor(s): Takashi Yanagisawa, Izumi Hase, Yasumoto TanakaAbstractWe investigated quantized modes of kinks in the phase space of superconducting gaps in a superconductor with multiple gaps. The kink is described by the sine-Gordon model in a two-gap superconductor and by the double sine-Gordon model in a three-gap superconductor. A fractional-flux vortex exists at the edge of the kink, and a fractional-flux vortex will be stable in a three-gap superconductor with time-reversal symmetry breaking. The kink and fractional-flux vortex exhibit massless modes as a sliding motion. We show further that there are one zero-energy mode (massless mode) and quantized excitation modes in kinks, which are characteristic features o...Physics Letters AjournalsSat, 20 Oct 2018 19:09:32 +0100612239213The investigation of structural, electronic, elastic and thermodynamic properties of Gd1−xYxAuPb alloys: A first principle study
https://medworm.com/612239212/the-investigation-of-structural-electronic-elastic-and-thermodynamic-properties-of-gd1xyxaupb-a/
Publication date: Available online 19 October 2018Source: Physics Letters AAuthor(s): Parviz Saeidi, Shahram Yalameha, Zahra NourbakhshAbstractFirst principle calculations have been employed to investigate the effects of Y concentration, pressure and temperature on various properties of Gd1−xYxAuPb (x=0,0.25,0.5,0.75,1) alloys using density functional theory (DFT). The full potential linearized augmented plane wave (FP-LAPW) method within a framework of the generalized gradient approximation (GGA) is used to perform the calculated results of this paper. Phase stability of Gd1−xYxAuPb alloys is studied using the total energy versus unit cell volume calculations. The equilibrium lattice parameters of these alloys are in good agreement with the available experimental results. The mechanic...Physics Letters AjournalsSat, 20 Oct 2018 19:09:32 +0100612239212Temperature control of spin wave propagation over 100 μm distance in 100 nm-thick YIG film
https://medworm.com/611621320/temperature-control-of-spin-wave-propagation-over-100-m-distance-in-100-nm-thick-yig-film/
Publication date: Available online 18 October 2018Source: Physics Letters AAuthor(s): Md Shah Alam, Chuangtang Wang, Jilei Chen, Jianyu Zhang, Chuanpu Liu, Jiang Xiao, Yizheng Wu, Lei Bi, Haiming YuAbstractThe spin wave propagating along a film of 100 nm- thick yttrium iron garnet is studied with temperature control. Using a vector network analyzer, temperature dependence of spin wave transmission is measured. We observe a clear resonance frequency shift of 210 MHz with temperature change of 40 K. This can be explained by the dispersion variation of the temperature. These results enable a complete pass or forbidden spin wave propagation in a certain frequency window with temperature control which might lead to application of spin wave filters. (Source: Physics Letters A)Physics Letters AjournalsFri, 19 Oct 2018 14:39:29 +0100611621320Exotic vortex structures of the dipolar Bose-Einstein condensates trapped in harmonic-like and toroidal potential
https://medworm.com/611621319/exotic-vortex-structures-of-the-dipolar-bose-einstein-condensates-trapped-in-harmonic-like-and-toroi/
Publication date: Available online 18 October 2018Source: Physics Letters AAuthor(s): Rui-Fang Zhang, Xiao-Fei Zhang, Lu LiAbstractBased on the tunable intensity and waist of Gaussian laser, harmonic-like and toroidal potentials can be achieved and the ground-state properties of the dipolar Bose-Einstein condensate (BEC) trapped in such potentials are investigated. It is found that, in the harmonic-like potential, the singly and doubly quantized vortices can exist in the scale condensate and translate respectively into vortex pairs and triangular vortex lattice with increasing dipole-dipole interaction (DDI). Especially, the sandwich-like structure can be observed in the ground-state density profiles by tuning the direction and strength of DDI for some rotating frequency. In the toroidal p...Physics Letters AjournalsFri, 19 Oct 2018 14:39:29 +0100611621319On symmetry preserving and symmetry broken bright, dark and antidark soliton solutions of nonlocal nonlinear Schrödinger equation
https://medworm.com/611212271/on-symmetry-preserving-and-symmetry-broken-bright-dark-and-antidark-soliton-solutions-of-nonlocal-n/
We present explicit one and two bright soliton solutions and show that they exhibit stable structures only when we combine the field and parity transformed complex conjugate field. Further, we derive two dark/antidark soliton solution with the help of DT method. Unlike the bright soliton case, dark/antidark soliton solution exhibits stable structure for the field and the parity transformed conjugate field separately. In the dark/antidark soliton solution case we observe a contrasting behaviour between the envelope of the field and parity transformed complex conjugate envelope of the field. For a particular parametric choice, we get dark (antidark) soliton for the field while the parity transformed complex conjugate field exhibits antidark (dark) soliton. Due to this surprising result, both...Physics Letters AjournalsThu, 18 Oct 2018 19:30:34 +0100611212271Oxygen vacancy-assisted high ionic conductivity in perovskite LaCoO3−δ (δ = 1/3) thin film: A first-principles-based study
https://medworm.com/610596653/oxygen-vacancy-assisted-high-ionic-conductivity-in-perovskite-lacoo3-13-thin-film-/
Publication date: Available online 17 October 2018Source: Physics Letters AAuthor(s): Hong Wu, Feng LiAbstractSynthesizing a solid state material with high oxygen-ionic conductivity is a challenge. In this work, an integrated method of density functional theory and first-principles molecular dynamics (FPMD) simulations has been performed to investigate the oxygen-ionic conductivity in the LaCoO3−δ films. We demonstrated that, in the strained epitaxial LaCoO3−δ films, O vacancy superstructures release strain and produce the high oxygen-ionic conductivity with an activation barrier of 0.65±0.1 eV. We found that the oxygen hopping occurs in the oxygen-deficient regions of CoO mainly. We proposed a possible oxygen-ionic diffusion highway with an energy barrier of 0.55 eV by using the tr...Physics Letters AjournalsWed, 17 Oct 2018 14:42:31 +0100610596653Structural, magnetic, magnetocaloric and impedance spectroscopy analysis of Pr0.8Sr0.2MnO3 manganite prepared by modified solid-state route
https://medworm.com/610183328/structural-magnetic-magnetocaloric-and-impedance-spectroscopy-analysis-of-pr08sr02mno3-manganite/
Publication date: Available online 15 October 2018Source: Physics Letters AAuthor(s): A. Ben Jazia Kharrat, K. Khirouni, W. BoujelbenAbstractOrthorhombic Pr0.8Sr0.2MnO3 sample is prepared by solid-state reaction method and quenched in water. The occurrence of a second-order phase transition is confirmed by Arrott plots. The critical exponents determined using different models are in good agreement with the 3D-Ising model. The magnetocaloric results have shown an important maximum of the magnetic entropy change and relative cooling power evaluated at 2.14 J kg−1 K−1 and 101.52 J kg−1 under a field change of 2T. The DC conductance measurements revealed that this compound exhibited a semiconductor to metallic behavior at TSM=400 K. Moreover, the AC results are described by the Jon...Physics Letters AjournalsTue, 16 Oct 2018 19:24:33 +0100610183328Editors
https://medworm.com/610183316/editors/
Publication date: 30 November 2018Source: Physics Letters A, Volume 382, Issue 47Author(s): (Source: Physics Letters A)Physics Letters AjournalsTue, 16 Oct 2018 19:24:33 +0100610183316Stability and coherence of strong-coupling magneto-bipolaron in asymmetric quantum dot under laser field effect
https://medworm.com/609560936/stability-and-coherence-of-strong-coupling-magneto-bipolaron-in-asymmetric-quantum-dot-under-laser-f/
This study enables to construct superconducting materials. (Source: Physics Letters A)Physics Letters AjournalsMon, 15 Oct 2018 14:21:29 +0100609560936Critical and multicritical behavior in the Ising–Heisenberg universality class
https://medworm.com/609560935/critical-and-multicritical-behavior-in-the-isingheisenberg-universality-class/
Publication date: Available online 12 October 2018Source: Physics Letters AAuthor(s): A.O. SorokinAbstractCritical behavior of three-dimensional classical frustrated antiferromagnets with a collinear spin ordering and with an additional twofold degeneracy of the ground state is studied. We consider two lattice models, whose continuous limit describes a single phase transition with a symmetry class differing from the class of non-frustrated magnets as well as from the classes of magnets with non-collinear spin ordering. A symmetry breaking is described by a pair of independent order parameters, which are similar to order parameters of the Ising and O(N) models correspondingly. Using the renormalization group method, it is shown that a transition is of first order for non-Ising spins. For Is...Physics Letters AjournalsMon, 15 Oct 2018 14:21:29 +0100609560935Ultracold Rydberg Atoms for Efficient Storage of Terahertz Frequency Signals using Electromagnetically Induced Transparency
https://medworm.com/607485842/ultracold-rydberg-atoms-for-efficient-storage-of-terahertz-frequency-signals-using-electromagnetical/
Publication date: Available online 11 October 2018Source: Physics Letters AAuthor(s): Sumit Bhushan, Vikas S. Chauhan, Raghavan K. EaswaranAbstractQuantum communication with terahertz (THz) frequency signals has many advantages like reduced attenuation and scintillation effects in certain atmospheric conditions along with very high level of data security. In this work, we propose a scheme to realize Quantum Memory (QM) for efficient storage of terahertz (THz) frequency signals using Electromagnetically Induced Transparency (EIT) in an ultracold atomic medium of 87Rb Rydberg atoms prepared in a Two Dimensional Magneto Optical Trap (2D-MOT). The uniqueness of our scheme lies in the choice of the energy levels involved in the EIT process, all three of which have been chosen to be the Rydberg ...Physics Letters AjournalsThu, 11 Oct 2018 14:09:36 +0100607485842A theoretical prediction of rotating waves in Type-I hydraulic jumps
https://medworm.com/607076998/a-theoretical-prediction-of-rotating-waves-in-type-i-hydraulic-jumps/
Publication date: Available online 9 October 2018Source: Physics Letters AAuthor(s): Arnab K. Ray, Niladri Sarkar, Abhik Basu, Jayanta K. BhattacharjeeAbstractThe rotation of polygons in a Type-II hydraulic jump prompts us to look for a rotational feature in the Type-I hydraulic jump. Coupling the radial and azimuthal flows breaks the azimuthal symmetry of the shallow-water circular jump. An unstable rotating wave along the circumference of the jump is possible with a kinematic viscosity of very small order, whose upper threshold value is less than the kinematic viscosity of water. (Source: Physics Letters A)Physics Letters AjournalsWed, 10 Oct 2018 19:12:38 +0100607076998Extreme Narrow Escape: shortest paths for the first particles among n to reach a target window
https://medworm.com/607076996/extreme-narrow-escape-shortest-paths-for-the-first-particles-among-n-to-reach-a-target-window/
Publication date: Available online 10 October 2018Source: Physics Letters AAuthor(s): K. Basnayake, A. Hubl, Z. Schuss, D. HolcmanAbstractWhat are the paths associated with the fastest Brownian particles that reach a narrow window located on the boundary of a microdomain? Although the distribution of the fastest arrival times has been well studied in dimension 1, much less is known in higher dimensions. Based on the Wiener path-integral, we suggest that the paths of the fastest particle are concentrated near the shortest paths that minimize the energy-action. Stochastic simulations confirm the present result when an obstacle is positioned between the source point and a narrow window. To conclude paths associated with the fastest arrival times differ significantly from the ones of mean prop...Physics Letters AjournalsWed, 10 Oct 2018 19:12:38 +0100607076996Editors
https://medworm.com/607076982/editors/
Publication date: 23 November 2018Source: Physics Letters A, Volume 382, Issue 46Author(s): (Source: Physics Letters A)Physics Letters AjournalsWed, 10 Oct 2018 19:12:38 +0100607076982Stability of symmetry breaking states in finite-size Dicke model with photon leakage
https://medworm.com/607076977/stability-of-symmetry-breaking-states-in-finite-size-dicke-model-with-photon-leakage/
Publication date: 23 November 2018Source: Physics Letters A, Volume 382, Issue 46Author(s): R. Imai, Y. YamanakaAbstractWe investigate the finite-size Dicke model with photon leakage. It is shown that the symmetry breaking states, which are characterized by non-vanishing 〈aˆ〉≠0 and correspond to the ground states in the superradiant phase in the thermodynamic limit, are stable, while the eigenstates of the isolated finite-size Dicke Hamiltonian conserve parity symmetry. We introduce and analyze an effective master equation that describes the dynamics of a pair of the symmetry breaking states that are the degenerate lowest energy eigenstates in the superradiant region with photon leakage. It becomes clear that photon leakage is essential to stabilize the symmetry breaking states and ...Physics Letters AjournalsWed, 10 Oct 2018 19:12:38 +0100607076977On subgame perfect equilibria in quantum Stackelberg duopoly with incomplete information
https://medworm.com/606450702/on-subgame-perfect-equilibria-in-quantum-stackelberg-duopoly-with-incomplete-information/
Publication date: Available online 6 October 2018Source: Physics Letters AAuthor(s): Piotr Fra̧ckiewiczAbstractThe Li–Du–Massar quantum duopoly model is one of the generally accepted quantum game schemes. It has applications in a wide range of duopoly problems. Our purpose is to study Stackelberg's duopoly with incomplete information in the quantum domain. The result of Lo and Kiang has shown that the correlation of players' quantities caused by the quantum entanglement enhances the first-mover advantage in the game. Our work demonstrates that there is no first-mover advantage if the players' actions are maximally correlated. Furthermore, we proved that the second mover gains a higher equilibrium payoff than the first one. (Source: Physics Letters A)Physics Letters AjournalsTue, 09 Oct 2018 14:39:36 +0100606450702Correlation between Hydrogen/Deuterium Exchange and Amide I Band Intensity in Hemoglobin Aqueous Solution under Static or 50 Hz Magnetic Field
https://medworm.com/606450701/correlation-between-hydrogendeuterium-exchange-and-amide-i-band-intensity-in-hemoglobin-aqueous-sol/
Publication date: Available online 9 October 2018Source: Physics Letters AAuthor(s): Emanuele Calabrò, Salvatore MagazùAbstractSamples of hemoglobin in deuterium oxide solution (D2O) and in bidistilled H2O water solution, both at the concentration of 100 mg/ml, were exposed to a static magnetic field at 100 mT; analogue samples were exposed to 50 Hz magnetic field at 1 mT. Fourier Transform Infrared (FTIR) Spectroscopy was used to analyze separately the response of the secondary structure of this protein (diluted in both aqueous solutions) to separated exposure to both magnetic fields. The most relevant result which was observed after exposures was the significant increasing in intensity of the Amide I band, which was already explained in previous studies assuming that proteins α-helix ...Physics Letters AjournalsTue, 09 Oct 2018 14:39:36 +0100606450701Generalized squeezed states
https://medworm.com/605206577/generalized-squeezed-states/
Publication date: Available online 5 October 2018Source: Physics Letters AAuthor(s): Kevin Zelaya, Sanjib Dey, Véronique HussinAbstractSqueezed states are one of the most useful quantum optical models having various applications in different areas, especially in quantum information processing. Generalized squeezed states are even more interesting since, sometimes, they provide additional degrees of freedom in the system. However, they are very difficult to construct and, therefore, people explore such states for individual setting and, thus, a generic analytical expression for generalized squeezed states is yet inadequate in the literature. In this article, we propose a method for the generalization of such states, which can be utilized to construct the squeezed states for any kind of qua...Physics Letters AjournalsSun, 07 Oct 2018 05:12:38 +0100605206577On subgame perfect equilibria in quantum Stackelberg duopoly with incompete information
https://medworm.com/605206576/on-subgame-perfect-equilibria-in-quantum-stackelberg-duopoly-with-incompete-information/
Publication date: Available online 6 October 2018Source: Physics Letters AAuthor(s): Piotr Fra̧ckiewiczAbstractThe Li-Du-Massar quantum duopoly model is one of the generally accepted quantum game schemes. It has applications in a wide range of duopoly problems. Our purpose is to study Stackelberg's duopoly with incomplete information in the quantum domain. The result of Lo and Kiang has shown that the correlation of players' quantities caused by the quantum entanglement enhances the first-mover advantage in the game. Our work demonstrates that there is no first-mover advantage if the players' actions are maximally correlated. Furthermore, we proved that the second mover gains a higher equilibrium payoff than the first one. (Source: Physics Letters A)Physics Letters AjournalsSun, 07 Oct 2018 05:12:38 +0100605206576Scaling invariance in a social network with limited attention and innovation
https://medworm.com/604789260/scaling-invariance-in-a-social-network-with-limited-attention-and-innovation/
We describe the behavior of the diversity of information in a social network as a function of time by using scaling arguments and we demonstrate its scaling invariant with respect of time as well as information load, attention and network sizes. Scaling transformations are used to overlap different curves of diversity, obtained by distinct parameters, onto an universal plot. (Source: Physics Letters A)Physics Letters AjournalsSat, 06 Oct 2018 10:12:28 +0100604789260Benefits of intervention in spatial public goods games
https://medworm.com/604789259/benefits-of-intervention-in-spatial-public-goods-games/
Publication date: Available online 4 October 2018Source: Physics Letters AAuthor(s): Luhe Yang, Zhaojin Xu, Lianzhong Zhang, Duoxing YangAbstractThe anarchy driven by private punishment is inopportune and inappropriate in modern human societies. It is necessary for a person to appeal to a higher authority such as the police so that a society can maintain more stable. We introduce strategy intervention instead of punishment in spatial public goods game. Some defectors are forced to contribute to the common pool. We show how strategy intervention affects cooperation of a population. Interestingly, weak intervention restrains the impact of spatial reciprocity leading to a lower level of cooperation or even a full defection state. Such phenomena are in contrast to ordinary intuitions. Interven...Physics Letters AjournalsSat, 06 Oct 2018 10:12:28 +0100604789259Electronic vacuum charge for an overcritical nucleus
https://medworm.com/604169883/electronic-vacuum-charge-for-an-overcritical-nucleus/
Publication date: Available online 21 September 2018Source: Physics Letters AAuthor(s): Sergey F. Garanin, Ekaterina M. KravetsAbstractA “cut-off” Coulomb potential taking into account the finite size of the nucleus is finite, and a solution of the Dirac equation can be constructed for any energy, both positive and negative. In the paper we develop an exact solution of the Dirac equation for a fixed value of the total momentum j for the whole spectrum of energies, which allows us to determine the vacuum charge and its spatial distribution. We consider nuclei with different charges Z, both Z<Zc and Z>Zc, where Z=Zc is the “critical” charge, at which the energy of the lowest discrete state reaches the boundary of the lower continuum ε=−mc2. Polarization of vacuum is determined...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169883Analysis of drivers' characteristics on continuum model with traffic jerk effect
https://medworm.com/604169882/analysis-of-drivers-characteristics-on-continuum-model-with-traffic-jerk-effect/
Publication date: Available online 25 September 2018Source: Physics Letters AAuthor(s): Zhai Cong, Wu WeitiaoAbstractIn this paper we propose an enhanced continuum model for traffic flow considering the effect of driver characteristics and traffic jerk. Based on the linear stability condition, the sufficient conditions of model stability is given. In the nonlinear stability analysis, we derive the KdV–Burger equation to describe the propagation characteristics of traffic density waves near the neutral stability curve. The simulation example verified that the driver characteristics and traffic jerk have a significant impact on the stability of the traffic flow and emissions. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169882Exact density matrix of an oscillator-bath system: Alternative derivation
https://medworm.com/604169881/exact-density-matrix-of-an-oscillator-bath-system-alternative-derivation/
Publication date: Available online 25 September 2018Source: Physics Letters AAuthor(s): Fardin KheirandishAbstractStarting from a total Lagrangian describing an oscillator-bath system, an alternative derivation of exact quantum propagator is presented. Having the quantum propagator, the exact density matrix, reduced density matrix of the main oscillator and thermal equilibrium fixed point are obtained. The modified quantum propagator is obtained in the generalised case where the main oscillator is under the influence of a classical external force. By introducing auxiliary classical external fields, the generalised quantum propagator or generating functional of position correlation functions is obtained. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169881Moment of inertia of superconductors
https://medworm.com/604169880/moment-of-inertia-of-superconductors/
Publication date: Available online 25 September 2018Source: Physics Letters AAuthor(s): J.E. HirschAbstractWe find that the bulk moment of inertia per unit volume of a metal becoming superconducting increases by the amount me/(πrc), with me the bare electron mass and rc=e2/mec2 the classical electron radius. This is because superfluid electrons acquire an intrinsic moment of inertia me(2λL)2, with λL the London penetration depth. As a consequence, we predict that when a rotating long cylinder becomes superconducting its angular velocity does not change, contrary to the prediction of conventional BCS-London theory that it will rotate faster. We explain the dynamics of magnetic field generation when a rotating normal metal becomes superconducting. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169880Influences of strains on the formation of the quasi-Dirac cone and the Landau levels in black phosphorus
https://medworm.com/604169879/influences-of-strains-on-the-formation-of-the-quasi-dirac-cone-and-the-landau-levels-in-black-phosph/
Publication date: Available online 26 September 2018Source: Physics Letters AAuthor(s): Zhaotan Jiang, Zengtao LvAbstractA tunable tight-binding (TB) Hamiltonian, which can be tuned continuously by applying the strains, is proposed based on the two tight-binding Hamiltonian models used to describle the pristine and compressed black phosphorus (BP). This tunable TB Hamiltonian should be of fundamental significance in two aspects: i) A general tunable TB Hamiltonian making it possible to study the BP more conveniently and deeply; ii) An extension of the study of the strain effect from the monolayer phosphorene to the multilayer phosphorene and even the bulk BP in the presence of both the in-plane and out-of-plane strains. Furthermore, based on the tunable TB Hamiltonian we can find the strai...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169879The first principle study of the electronic structure of SixGe(1−x) alloy films
https://medworm.com/604169878/the-first-principle-study-of-the-electronic-structure-of-sixge1x-alloy-films/
Publication date: Available online 1 October 2018Source: Physics Letters AAuthor(s): Xue-ke Wu, Wen-jing Chen, You-sheng Yu, Yan-lin TangAbstractFirst principles calculation based on density functional theory (DFT) with the generalized gradient approximation (GGA) are carried out to investigate the electronic band structures of SixGe(1−x) alloys nanofilms. The calculation results show that the band gaps of (100), (110) and (111) surfaces SixGe(1−x) alloy films with different thickness first increase with the increase of Si content, then flatten out, and finally decrease. At the same time, the transformation of direct band gap and indirect band gap occurs when the thickness of films and Si content of the three surface SixGe(1−x) alloy films changes to a certain critical condition. It ...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169878Ultra-intense femtosecond super-heavy ion beams driven by a multi-PW laser
https://medworm.com/604169877/ultra-intense-femtosecond-super-heavy-ion-beams-driven-by-a-multi-pw-laser/
Publication date: Available online 1 October 2018Source: Physics Letters AAuthor(s): Jarosław Domański, Jan BadziakAbstractThe paper reports the results of numerical studies on the laser-driven acceleration of super-heavy ions by a multi-PW laser pulse of ultra-relativistic intensity attainable with the Extreme Light Infrastructure lasers currently being built in Europe. Using a multi-dimensional (2D3V) particle-in-cell code, it is shown that multi-GeV super-heavy (thorium) ion beams with an intensity of ∼1021–1022W/cm2, fluence ∼1017–1018cm−2 and time duration ∼20–100fs can be produced from a sub-μm thorium target irradiated by a 150-J, 20-fs laser pulse with an intensity of 1023W/cm2. Such ion beams are impossible to obtain presently with the use of conventional RF-drive...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169877Study of EIT resonances in an anti-relaxation coated Rb vapor cell
https://medworm.com/604169876/study-of-eit-resonances-in-an-anti-relaxation-coated-rb-vapor-cell/
Publication date: Available online 1 October 2018Source: Physics Letters AAuthor(s): Mangesh Bhattarai, Vineet Bharti, Vasant Natarajan, Armen Sargsyan, David SarkisyanAbstractWe study the sign of resonances obtained in electromagnetically induced transparency (EIT). Resonances of both kinds—bright (corresponding to enhanced absorption) and dark (corresponding to reduced absorption)—are obtained when the frequency of a probe beam is scanned. The experimental results, presented earlier, use magnetic sublevels of a hyperfine transition in the D1 line of 87Rb along with a magnetic field of 27 G. The atoms are contained in a vapor cell at room temperature, and with anti-relaxation coating on the walls. A quantitative theoretical model, which reproduces the experimental results quite well, ...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169876Six-dimensional heavenly equation. Dressing scheme and the hierarchy
https://medworm.com/604169875/six-dimensional-heavenly-equation-dressing-scheme-and-the-hierarchy/
Publication date: Available online 2 October 2018Source: Physics Letters AAuthor(s): L.V. Bogdanov, M.V. PavlovAbstractWe consider six-dimensional heavenly equation as a reduction in the framework of general six-dimensional linearly degenerate dispersionless hierarchy. We characterise the reduction in terms of wave functions, introduce generating relation, Lax–Sato equations and develop the dressing scheme for the reduced hierarchy. Using the dressing scheme, we construct a class of solutions for six-dimensional heavenly equation in terms of implicit functions. (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169875System of interacting harmonic oscillators in rotationally invariant noncommutative phase space
https://medworm.com/604169874/system-of-interacting-harmonic-oscillators-in-rotationally-invariant-noncommutative-phase-space/
Publication date: Available online 2 October 2018Source: Physics Letters AAuthor(s): Kh.P. GnatenkoAbstractRotationally invariant space with noncommutativity of coordinates and noncommutativity of momenta of canonical type is considered. A system of N interacting harmonic oscillators in uniform field and a system of N particles with harmonic oscillator interaction are studied. We analyze effect of noncommutativity on the energy levels of these systems. It is found that influence of coordinates noncommutativity on the energy levels of the systems increases with increasing of the number of particles. The spectrum of N free particles in uniform field in rotationally invariant noncommutative phase space is also analyzed. It is shown that the spectrum corresponds to the spectrum of a system of ...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169874Nonlocality and local causality in the Schrödinger equation with time-dependent boundary conditions
https://medworm.com/604169873/nonlocality-and-local-causality-in-the-schrdinger-equation-with-time-dependent-boundary-conditions/
Publication date: Available online 2 October 2018Source: Physics Letters AAuthor(s): A. Matzkin, S.V. Mousavi, M. WaegellAbstractWe investigate the nonlocal dynamics of a single particle placed in an infinite well with moving walls. It is shown that in this situation, the Schrödinger equation (SE) violates local causality by causing instantaneous changes in the probability current everywhere inside the well. This violation is formalized by designing a gedanken faster-than-light communication device which uses an ensemble of long narrow cavities and weak measurements to resolve the weak value of the momentum far away from the movable wall. Our system is free from the usual features causing nonphysical violations of local causality when using the (nonrelativistic) SE, such as instantaneous ...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169873Spin-polarized transport induced by photoirradiation in zigzag silicene nanosystem
https://medworm.com/604169872/spin-polarized-transport-induced-by-photoirradiation-in-zigzag-silicene-nanosystem/
Publication date: Available online 3 October 2018Source: Physics Letters AAuthor(s): Yun-Lei Sun, Xing-Bo Wang, En-Jia YeAbstractWe study the spin-polarized transport induced by photoirradiation in zigzag silicene nanosystem, based on tight-binding approach, Green's function method and Landauer–Büttiker formula. By applying strong circular polarized light, silicene nanosystem can be transformed into a quantum Hall insulator, where the spin-down subband is gapped while the spin-up subband persists gapless edge state. Therefore, the dc conductance is dominated by the spin-up electrons, and the spin polarization can reach almost 100% around the Fermi energy. The spatial-resolved local density of states confirm that the spin-up electrons transport at two edges of the nanosystem in opposite ...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169872Domain wall nucleation and propagation in spin-transfer torque switching with thermal effects
https://medworm.com/604169871/domain-wall-nucleation-and-propagation-in-spin-transfer-torque-switching-with-thermal-effects/
Publication date: Available online 3 October 2018Source: Physics Letters AAuthor(s): Bingjin Chen, Tiejun Zhou, Siang Yee Sim, Sze Ter Lim, Hao GongAbstractWe conduct micro-magnetic simulations to study spin-transfer torque induced magnetization switching in perpendicular magnetic tunneling junctions. The effects of current densities and temperatures on the switching processes are studied in details. We then proposed an approach to compute the deterministic switching time by taking thermal-effect into account. The switching time is less temperature-dependent under higher current density; however, as the current density decreases, the effect of temperature on the switching time becomes more and more significant. The switching process with micro-magnetic simulations is shown to be via domain...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169871Multiple internal resonances in MEMS arch resonators
https://medworm.com/604169870/multiple-internal-resonances-in-mems-arch-resonators/
Publication date: Available online 3 October 2018Source: Physics Letters AAuthor(s): A.Z. Hajjaj, N. Jaber, M.A.A. Hafiz, S. Ilyas, M.I. YounisAbstractMicromachined shallow arch resonant beams have attracted significant attention thanks to their rich dynamical behavior, inherent nonlinearities, and the potential to excite various internal resonances. Currently, there is a lack of comprehensive experimental studies for the various types of internal resonances in arches and particularly at the micro and nano scales. Here, we aim to investigate and identify different types of internal resonances of an initially curved beam, electrothermally actuated and electrostatically driven, by electrical characterization techniques. Upon changing the electrothermal voltage of silicon micromachined arches...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169870Editors
https://medworm.com/604169868/editors/
Publication date: 9 November 2018Source: Physics Letters A, Volume 382, Issue 44Author(s): (Source: Physics Letters A)Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169868A denial-of-service attack on fiber-based continuous-variable quantum key distribution
https://medworm.com/604169849/a-denial-of-service-attack-on-fiber-based-continuous-variable-quantum-key-distribution/
Publication date: 16 November 2018Source: Physics Letters A, Volume 382, Issue 45Author(s): Yuan Li, Peng Huang, Shiyu Wang, Tao Wang, Dengwen Li, Guihua ZengAbstractIn a fiber-based continuous-variable quantum key distribution (CVQKD) system, to perform the channel estimation, the channel transmittance is usually assumed to be a constant. Subsequently, when the channel parameters are intentionally manipulated, the employed parameter estimation method will lead to deviations of channel parameters and ultimately impacting the evaluation of the secret key rate. In this paper, we propose a denial-of-service attack strategy based on Eve's manipulation of the channel parameters. In particular, we analyze in detail the impact of this attack when the channel transmittance is attacked and obeys tw...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169849Toward a topological scenario for high-temperature superconductivity of copper oxides
https://medworm.com/604169845/toward-a-topological-scenario-for-high-temperature-superconductivity-of-copper-oxides/
Publication date: 16 November 2018Source: Physics Letters A, Volume 382, Issue 45Author(s): V.A. Khodel, J.W. Clark, M.V. ZverevAbstractThe structure of the joint phase diagram demonstrating high-Tc superconductivity of copper oxides is studied on the basis of the theory of interaction-induced flat bands. Prerequisites for an associated topological rearrangement of the Landau state are established, and related non-Fermi-liquid (NFL) behavior of the normal states of cuprates is investigated. We focus on manifestations of this behavior in the electrical resistivity ρ(T), especially the observed gradual crossover from normal-state T-linear behavior ρ(T,x)=A1(x)T at doping x below the critical value xch of hole doping for termination of superconductivity, to T-quadratic behavior at x>xch, wh...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169845Possible higher temperature superconductivity in the modulation-doped superlattice structure of cuprate superconductors
https://medworm.com/604169844/possible-higher-temperature-superconductivity-in-the-modulation-doped-superlattice-structure-of-cupr/
Publication date: 16 November 2018Source: Physics Letters A, Volume 382, Issue 45Author(s): Kazuhisa NishiAbstractWe design a new structure for a cuprate superconductor indicating the possibility of higher temperature superconductivity using our recently proposed composite fermions theory. It is constructed with modulation-doped superlattice structures, which are often used in the design of semiconductor superlattice devices. The superconductive critical temperature (Tc) was calculated in the superlattice structures of the superconductor in which the optimal doped CuO2 layer was sandwiched between two less-doped CuO2 layers. We find that if these structures could be realized in a cuprate superconductor such as Bi2Sr2Ca2Cu3O10 or HgBa2Ca2Cu3O9, the highest Tc could attain the level of 300 K...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169844Combined effect of the perpendicular magnetic field and dilute charged impurity on the electronic phase of bilayer AA-stacked hydrogenated graphene
https://medworm.com/604169843/combined-effect-of-the-perpendicular-magnetic-field-and-dilute-charged-impurity-on-the-electronic-ph/
Publication date: 16 November 2018Source: Physics Letters A, Volume 382, Issue 45Author(s): Bui Dinh Hoi, Mohsen YarmohammadiAbstractWe address the electronic phase engineering in the impurity-infected functionalized bilayer graphene with hydrogen atoms (H-BLG) subjected to a uniform Zeeman magnetic field, employing the tight-binding model, the Green's function technique, and the Born approximation. In particular, the key point of the present work is focused on the electronic density of states (DOS) in the vicinity of the Fermi energy. By exploiting the perturbative picture, we figure out that how the interaction and/or competition between host electrons, guest electrons, and the magnetic field potential can lead to the phase transition in H-BLG. Furthermore, different configurations of hy...Physics Letters AjournalsFri, 05 Oct 2018 05:18:37 +0100604169843Coupling field dependent quantum interference effects in a Λ-system of 87Rb atom
https://medworm.com/602555880/coupling-field-dependent-quantum-interference-effects-in-a-system-of-87rb-atom/
Publication date: Available online 20 September 2018Source: Physics Letters AAuthor(s): Charu Mishra, A. Chakraborty, Vivek Singh, S.P. Ram, V.B. Tiwari, S.R. MishraAbstractA Λ-system in D2 line transition of the R87b atom has been investigated for quantum interference effects for different configurations of coupling field. With a travelling wave coupling field (co-propagating with probe field), the probe beam shows the earlier known electromagnetically induced transparency (EIT) effect at the resonance. With a standing wave coupling field (which is co- and counter-propagating with probe beam), the probe EIT gets transformed into an electromagnetically induced absorption (EIA). A variation in coupling beam power has shown that, at high coupling power, EIA signals have much larger amplitud...Physics Letters AjournalsFri, 21 Sep 2018 16:21:31 +0100602555880Magnetocaloric properties of the spin-S (S ≥ 1) Ising model on a honeycomb lattice
https://medworm.com/602555879/magnetocaloric-properties-of-the-spin-s-s1-ising-model-on-a-honeycomb-lattice/
Publication date: Available online 20 September 2018Source: Physics Letters AAuthor(s): Ümit Akinci, Y. Yüksel, E. VatanseverAbstractUsing effective field theory, we have investigated magnetocaloric features of the spin-S Ising model for some spin values S=1,3/2,2,5/2,3 and 7/2 on a honeycomb lattice. Effects of the external magnetic field on the isothermal entropy change, its half-width and also cooling capacity have been determined and discussed in detail. The numerical results show that the isothermal entropy change decreases whereas its half-width and cooling capacity tends to increase when the spin magnitude of the system is increased starting from S=1 to 7/2 for a fixed value of the external field. Finally, we have also performed some calculations to check the applicability of magn...Physics Letters AjournalsFri, 21 Sep 2018 16:21:31 +0100602555879Topological phase transition in the quasiperiodic disordered Su–Schriffer–Heeger chain
https://medworm.com/602555878/topological-phase-transition-in-the-quasiperiodic-disordered-suschrifferheeger-chain/
Publication date: Available online 20 September 2018Source: Physics Letters AAuthor(s): Tong Liu, Hao GuoAbstractWe study the stability of the topological phase in one-dimensional Su–Schrieffer–Heeger chain subject to the quasiperiodic hopping disorder. Two different hopping disorder configurations are investigated, one is the Aubry–André quasiperiodic disorder without mobility edges and the other is the slowly varying quasiperiodic disorder with mobility edges. Interestingly, we find topological phase transitions occur at the critical quasiperiodic disorder strengths which have an exact linear relation with the dimerization strengths for both disorder configurations. We further investigate the localized property of the Su–Schrieffer–Heeger chain with the slowly varying quasiper...Physics Letters AjournalsFri, 21 Sep 2018 16:21:31 +0100602555878Partial structural restoring of two-qubit transferred state
https://medworm.com/602353714/partial-structural-restoring-of-two-qubit-transferred-state/
Publication date: Available online 19 September 2018Source: Physics Letters AAuthor(s): A.I. ZenchukAbstractWe consider the communication line with two-qubit sender and receiver, the later is embedded into the four-qubit extended receiver. Using the optimizing unitary transformation on the extended receiver we restore the structure of the non-diagonal part of an arbitrary initial sender's state at the remote receiver at certain time instant. Obstacles for restoring the diagonal part are discussed. We represent examples of such structural restoring in a communication line of 42 spin-1/2 particles. (Source: Physics Letters A)Physics Letters AjournalsFri, 21 Sep 2018 06:42:41 +0100602353714Dynamics of mixed lump-solitary waves of an extended (2 + 1)-dimensional shallow water wave model
https://medworm.com/602353713/dynamics-of-mixed-lump-solitary-waves-of-an-extended-21-dimensional-shallow-water-wave-mode/
Publication date: Available online 19 September 2018Source: Physics Letters AAuthor(s): Harun-Or-Roshid, Wen-Xiu MaAbstractTo explore the features of lump solutions, which are local in every direction of space, a (2+1)-dimensional extended shallow water wave model is studied, based on its bilinear representation. Several ansatze have been utilized to determine single lump waves, lump-kink waves, single kinks and multi-lumps leading to breathers in terms of function patterns for the model. Through analyzing interactions between solitons, the impact of free parameters involved in the solutions on interaction types is exhibited. We determine a condition on the parameters under which a single kink wave can be converted into a multi-lump wave. To illustrate the interaction of exponential and pe...Physics Letters AjournalsFri, 21 Sep 2018 06:42:41 +0100602353713Effect of electric field on the electrical conductivity of defected carbon nanotube: Multifractal properties of the wavefunctions
https://medworm.com/602353712/effect-of-electric-field-on-the-electrical-conductivity-of-defected-carbon-nanotube-multifractal-pr/
Publication date: Available online 19 September 2018Source: Physics Letters AAuthor(s): S. Behnia, F. RahimiAbstractA theoretical analysis of controllable metal–insulator transition is performed by carrying out a quantum chaos analysis for a single-walled carbon nanotube which is affected by topological Stone–Wales defect. Nanotubes have recently attracted attention as promising materials for flexible nanoelectronic devices. Individual topological Stone–Wales defects have been identified experimentally in carbon nanotubes (CNTs) and graphene. The findings reveal that defected CNT displays a gradual crossover from metal to insulator phase in a longitudinal electric field. By determining the threshold value of the electric field for metal–insulator transition, CNT may be used as a sw...Physics Letters AjournalsFri, 21 Sep 2018 06:42:41 +0100602353712Energy content in linear mechanical systems with arbitrary time dependence
https://medworm.com/602353711/energy-content-in-linear-mechanical-systems-with-arbitrary-time-dependence/
Publication date: Available online 19 September 2018Source: Physics Letters AAuthor(s): M. Fernandez-GuastiAbstractA novel complementary variables formulation, permits the obtainment of invariants of a mechanical system following the rationale of Abel's differential equation identity. This approach allows for the decomposition of the total energy of the system into the energy of the object and the dynamic energy of the field. The force acting on the object must be linear in the spatial variable but is arbitrary in the time variable. Several examples, such as the time dependent harmonic oscillator and a swing are described with this complementary variables formulation. The exact solution for the energy of a Lorentz pendulum with uniformly varying length is presented. (Source: Physics Letter...Physics Letters AjournalsFri, 21 Sep 2018 06:42:41 +0100602353711A transformation theory for camouflaging arbitrary heat sources
https://medworm.com/599425855/a-transformation-theory-for-camouflaging-arbitrary-heat-sources/
Publication date: Available online 14 September 2018Source: Physics Letters AAuthor(s): Liujun Xu, Jiping HuangAbstractCamouflage devices have attracted intensive research interest for their significant applications. However, most camouflage devices are specifically designed according to target heat sources. Here, by applying the transformation thermotics approach, we develop a coordinate transformation, and design an unspecific camouflage device which can camouflage arbitrary heat sources into a circular one with an anisotropic shell. We verify the ability of our unspecific camouflage device with both steady and transient simulations. We also find the “apparent negative thermal conductivity” under certain conditions without violating the second law of thermodynamics. To ensure the fea...Physics Letters AjournalsSat, 15 Sep 2018 17:09:35 +0100599425855Effect of Coulomb repulsion on spin and orbital magnetism of cobalt–benzene complex: A relativistic density functional study
https://medworm.com/598367967/effect-of-coulomb-repulsion-on-spin-and-orbital-magnetism-of-cobaltbenzene-complex-a-relativisti/
Publication date: Available online 12 September 2018Source: Physics Letters AAuthor(s): M. Afshar, M. HematiAbstractWe have demonstrated electronic configurations and magnetic properties of single Co adatom on benzene (Bz) molecule in the framework of relativistic density functional theory. A sequence of fixed spin moment (FSM) calculations were carried out with and without Coulomb repulsion (U). We have investigated that varying the strength of Coulomb repulsion results to different equilibrium positions for the Co adatom on benzene molecule. It was shown that inclusion of the on-site Coulomb repulsion in the Co 3d orbitals affects significantly the geometry of Co–Bz complex. We also found two stable low-spin and high-spin multiplicities for the complex. The nature of the high-spin conf...Physics Letters AjournalsThu, 13 Sep 2018 17:24:35 +0100598367967Tailoring steep density profile with unstable points
https://medworm.com/598367966/tailoring-steep-density-profile-with-unstable-points/
Publication date: Available online 12 September 2018Source: Physics Letters AAuthor(s): Shun Ogawa, Xavier Leoncini, Alexei Vasiliev, Xavier GarbetAbstractThe mesoscopic properties of a plasma in a cylindrical magnetic field are investigated from the view point of test-particle dynamics. When the system has enough time and spatial symmetries, a Hamiltonian of a test particle is completely integrable and can be reduced to a single degree of freedom Hamiltonian for each initial state. The reduced Hamiltonian sometimes has unstable fixed points (saddle points) and associated separatrices. To choose among available dynamically compatible equilibrium states of the one particle density function of these systems we use a maximum entropy principle and discuss how the unstable fixed points affect t...Physics Letters AjournalsThu, 13 Sep 2018 17:24:35 +0100598367966Application of medium energy plasma focus device in study of radioisotopes
https://medworm.com/59836