Design of an Improved Optical Filter Based on Dual-Curved PCRR for WDM Systems

In this paper, an optical filter based on a two dimensional photonic crystal ring resonator (PCRR) with triangular lattice is designed and presented. For this purpose, the effects of positioning, arrangement and the number of the inner rods of the dual-curved PCRR on the performance characteristics of our optical filter such as the transmission coefficient and the quality factor have been fully investigated. Calculation results show that a transmission coefficient of 100% with a quality factor of 2400 at the operating wavelength of nearly 1576 nm can be achieved. The proposed optical filter comparatively performs better than the previously reported ones. In addition, this structure can be used for the design of optical multi-channel demultiplexer. To study the photonic band gap of our structure, the plane wave expansion (PWE) method has been used and the finite-difference time-domain (FDTD) method has also been employed to analyze the optical behavior of the proposed device.