Design and simulation of a planar integrated demultiplexer for coarse WDM

摘要

A planar integrated demultiplexer is designed for coarse wavelength division multiplexing (WDM) applications. The demultiplexer chip has no input or output waveguides, and simply consists of a single-mode slab waveguide and a concave reflective grating. The grating is strictly designed to diffract the multiplexed input light and focus different wavelengths on different positions on a cutting edge of the chip. A single-mode input fiber and some multi-mode output fibers are located on the cutting edge, being used as input and output channels. A numerical simulation is given to verify a design of an 8-channel CWDM chip. The results show that this demultiplexer has good focused output fields, a low loss, and a good spectral response with flat-top wide passband.