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) is obtained by varying Au nano-ring radius and other geometrical parameters. Our finite element method based 3D-COMSOL numerical simulations reveal that 12.24dB/μm (9.3dB/μm) extinction ratio per unit length can be achieved with (without) Au nano-rings considering r=80 nm; L=500 nm; and λ=1.56 um, respectively.

Source: Physics Letters A - July 9, 2019 Category: Physics Source Type: research