Optical wavelength demultiplexer based on photonic crystal ring resonators

Improving transmission efficiency, quality factor, channel spacing and crosstalk levels are the top priorities in designing optical demultiplexers, suitable for wavelength division multiplexing applications. In this paper, we proposed a novel structure for designing optical demultiplexer based on photonic crystal ring resonator. For performing wavelength selection task, we used four ring resonators. The resonance wavelength of the ring resonators depends on the dimensions of the ring core; therefore, we chose two different values for the lattice constant of the ring resonators core section. The channel spacing of the structure is about 3 nm, the minimum transmission efficiency is more than 95 %, the overall quality factor is more than 2,600, and finally the crosstalk levels are better than 19 dB.