Monolithic eight-wavelength demultiplexed receiver for dense WDM applications

A single chip incorporating a waveguide grating router and eight p-i-n photodetectors followed by eight preamplifiers constructed from heterojunction bipolar transistors, has been realized. The chip can demultiplex eight wavelengths spaced 100 GHz (0.81 nm) apart with nearest neighbor crosstalk better than -15 dB. The external quantum efficiency for each of the eight wavelength demultiplexed photodetectors was 5-8% (a responsivity of 0.06-0.10 A/W) and each optical front end operated up to 2.5 Gb/s. This is the first demonstration of monolithic integration of electronic circuits with a wavelength demultiplexer.>