Simulating Voltage-Dependent Index Changes in Silicon-on-Insulator Waveguides
应用文章
This application note demonstrates the simulation of voltage-dependent refractive index changes in silicon on insulator (SOI) waveguides using Keysight LaserMOD. The modeled device is a polysilicon ridge waveguide in a Modular Optic System (MOS) configuration. This setup enables rapid carrier accumulation near a thin buried oxide layer, supporting high-speed light modulation at 1.55 µm.
LaserMOD solves Poisson’s and carrier continuity equations to compute carrier densities, and the resulting index changes as a function of applied voltage. The simulations show how carrier accumulation near the oxide layer causes effective index shifts and phase changes, allowing for high-speed modulation with frequency responses above 2 GHz.
This approach provides key insights into the design of high-speed SOI modulators using carrier-induced electro-optic effects in Metal-Oxide-Semiconductor (MOS) waveguide structures.