Improvement of photonic crystal-based demultiplexer performance using two 90° bends

In recent years, optical devices based on photonic crystals have received much attention due to valuable features of photonic crystals such as low losses, very low group velocity, flexibility in shape and dimensions as well as being suitable for integrated circuits in Nano-scale. In this paper, using two-dimensional photonic crystals, the design of optical de-multiplexer as one of the most essential elements of integrated optical circuits, is investigated. For this purpose, an ultra-compact structure of resonator-based de-multiplexers is demonstrated and then by creating two high performance 90° bends along with engineering in the structure of bending wall rods at the output channels, transmission efficiency average 94.28%  in one of the output channels has been obtained.