Optimization of optical waveguide for optical DEMUX at optical windows

This paper investigates the structure, operation and simulation of Optical Waveguide for Optical Demultiplexer (DEMUX) at three optical communication windows. Optical waveguide is realized by 2D photonic crystal structure with 3 × 3 silicon rod. Photonic band gap of 2D photonic crystal structure is simulated by plane wave expansion method. Here, two types of reflections, external and internal are considered to obtain the photonic band gap. Simulation results reveal that lattice parameter and diameter of silicon rod play vital role to design the optical Demultiplexer. Again, this result showed that photonic crystal having diameter of silicon rod of 129 nm and lattice spacing of 428 nm allows wavelength, 850 nm, diameter 97 nm and 194 nm allows wavelength, 1310 nm, diameter 36 nm and lattice spacing of 180 allows wavelength, 1550 nm.