Horizontal Slot Waveguide for High-Performance Optical Modulator

Vanadium dioxide (VO2) is the most widely used phase change material for realizing electro-absorption modulators. VO2 undergoes a rapid phase transition from insulation to metallic phase when stimulated by an electric field larger than its threshold transition field. In this study, a three-layer slot waveguide modulator featuring a VO2 active layer for TM mode operation at a wavelength of
$\lambda=1.55\mu \mathrm{m}$
is designed. The proposed modulator employs ultra-thin silicon ion implant layers instead of metal contacts, resulting in a substantial improvement in modulator performance. Simulation results based on finite-difference time-domain (FDTD), reveal a high extinction ratio of about −10 dB.