Design channel add drop filter based on photonic crystal cavity resonator on GaAs substrate

Abstract

In this paper, we propose a new design of drop filter using photonic crystal cavity resonator on GAas. The proposed structure is composed of two photonic crystal waveguides and a photonic crystal resonant cavity with inner rods, scatterer rods and coupling, while the Central coupling rod had an elliptic geometry with a minimum radius and a maximum radius and some inclination. A special wave guide is introduce, it has a Sawtooth forms. Calculations of band structure and normalized transmission spectra are done by finite difference time domain method (FDTD). According to the results, we note that 95% dropping efficiency with quality factor of 258 is achievable at wavelength λ=1.578487 μm. The effect of adding a fifth port make us the efficacy 61% for the fourth with a Q factor of 79 for the 1.596mm wavelength and efficiency at the fifth port 78% and a Q factor of 138 for a 1.528mm wavelength.