Ridge waveguide quantum-well wavelength division demultiplexing detector with four channels

Abstract
The authors report a four-channel wavelength-division-demultiplexing detector based on a reverse-biased GaAs/AlGaAs single-quantum-well graded index separate confined heterostructure laser having segmented contacts. They achieve better than -15-dB channel crosstalk for three-wavelength operation, and better than -10-dB crosstalk for four-wavelength operation. The optimum wavelength separation is 18 nm for three channels and 14 nm for four channels. The authors show that by optimizing the segment lengths better performance can be obtained from the same layer structure.