Low Dimensional Channel Drop Filter for CWDM Optical Communication Networks

Abstract

This work presents salient features of an optical wavelength channel drop filter based on two-dimensional photonic crystal technology. The photonic band gap of two-dimensional Photonic Crystal (2-DPC) channel drop filter has been obtained by using plane wave expansion (PWE) method. The parameters of the channel drop filter have been optimized for telecommunication wavelengths 1611 nm and 1631 nm with a refractive index contrast of 3.79 and 3.96 using Gallium Antimonide (GaSb) dielectric material. The number of dielectric rods in X and Z directions were taken as 21, and 20, respectively with a spacing of 540 nm of having elliptical rod radius 0.15µm & 0.1 µm. The proposed design gives around 98% dropping efficiency with a good quality factor about 352. This ultra-compact structure is proposed which can be used for Coarse Wavelength Division Multiplexing (CWDM) applications and photonic integrated circuits.