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′ to Td phase. Moreover, we also analyze the superconductivity under high pressure based on BCS theory by calculating the density of states and phonon spectra. Our results may shed some light on understanding the relationship between the interlayer band occupancy and crystal stability of MoTe2 under high pressures.

Source: Physics Letters A - October 3, 2019 Category: Physics Source Type: research