Design and optimization of two dimensional photonic crystal based optical filter

In this paper, the channel drop filter based on two dimensional photonic crystal is proposed. The structure is made of silicon rods with the refractive index n 1 = 3.4641 which are perforated in air with refractive index n 2 = 1. The simulation results are obtained using 2D finite difference time domain (FDTD) method. The photonic band gap is calculated by plane wave expansion solver method. Resonant mode of the ring resonator and the filter transmission spectrum is calculated using 2D FDTD method. Full width half maximum (FWHM) bandwidth of the filter at the output transmission spectrum from 1.508 μm to 1.512 μm is 4 nm. The quality factor of the filter is 377.5 and the proposed filter design is around 21 × 15 μm which is suitable for photonic integrated circuits.