Design and simulation of high-quality factor all-optical demultiplexers based on a two-dimensional photonic crystal

Abstract

The present study proposes a new type of wavelength division multiplexing as an optical demultiplexer with four, eight, and sixteen output channels. The proposed structure consists of a two-dimensional square array of dielectric rods. The wavelength selection is performed by two defect rods and one defect with a rectangular cross-section. The values of the parameters related to each defect are selected so that the resonant wavelength associated with each output channel is located in the third telecommunication window (1.55μm). It is observed that the proposed demultiplexers demonstrate a high transmission efficiency and low crosstalk. As it is wanted to see just one sharp wavelength at the output of each channel, the quality factor needs to be maximized. Based on the results, the maximum values for demultiplexers with four, eight, and sixteen channels are 19863.89, 14264.57, and 32304.46, respectively. Due to the device’s small size, it can be used for wavelength division multiplexing (WDM) systems in photonic integrated circuits.