Phased-array wavelength demultiplexer withflattened wavelength response

Abstract
A four-channel phased-array wavelength demultiplexer with a flattened wavelength response has been realised for the first time in InP/InGaAsP at 1.54 µm by employing multimode output waveguides. The device has 2 nm channel spacing and a flat response (within 1 dB) of 1 nm.