An optical demultiplexer based on photonic crystal ring resonators

A 4-channel wavelength division demultiplexer based on photonic crystal ring resonators suitable for WDM applications is proposed in this paper. For performing the demultiplexing task, we used four resonant rings with different geometrical parameters. A square lattice of two dimensional photonic crystal structure composed of dielectric rods was used as fundamental structure for designing the demultiplexer, which has two photonic band gap regions. The first band gap covers the optical communication wavelengths. For this demultiplexer, the minimum transmission efficiency is more than 92% and average channel spacing is 3.2 nm.