Optical simulation of silicon-based complete photonic bandgap modulator

Abstract

We report on the design of a silicon-based 2D slab photonic crystal that operates around telecommunication wavelength (1550 nm). The design uses a honeycomb lattice and achieves a complete photonic bandgap (PBG) for transverse-magnetic (TM) polarized light while preserving a connected pattern for efficient electrical injection. The device operation is based on a dynamic shift of the complete photonic band-gap (PBG) due to induced change in the silicon refractive index by free carrier injection. The plane-wave expansion (PWE) method is utilized to design a honeycomb-lattice line defect photonic crystal waveguide with complete TM PBG. The light modulation performance of the device is simulated using the finite-difference time-domain (FDTD) method. With small size, rapid response time and high extinction ratio, the proposed optical modulator can be easily implemented to design ultra-compact all optical integrated circuits.