Athermal demodulator for 42.7-Gb/s DPSK signals

We report an athermal optical-delay-interferometer capable of demodulating any OC-768 DPSK signal on the ITU 50-GHz-grid over the C+L band. Receiver sensitivity of -35.5 dBm is achieved for a 42.7-Gb/s nonreturn-to-zero DPSK signal. (2 pages)