Numerical simulation of all optical demultiplexer based on pillar photonic crystal ring resonators

摘要

We present the numerical simulation of an all-optical demultiplexer using 2D photonic crystal ring resonators for optical communications systems. The structure consists of three ring resonators, one bus waveguide, and three drop waveguides. The photonic crystal of the demultiplexer has a square-shaped structure made up of silicon rods with lattice constant a=548nm, filling factor(r/a) of 0.18, where r is the radius of the rods, and linear refractive index of n=3.4. The structure can filter three standard wavelengths with 4.2nm channel spacing between the wavelengths. From the simulations, the mean quality factor and transmission efficiency of our structure are computed to be respectively 4936 and 96.5%, at wavelengths very close to 1.55m. The minimum and maximum values of crosstalk are -18.6dB and -34.6dB, respectively. The footprint of the device is 293.7m(2), which is suitable for photonic integrated circuits. The optical characteristics and the behavior of the proposed demultiplexer have been achieved by means of finite-difference time-domain (FDTD) method.