Parallel-Fed Traveling Wave Photodetector for > 100-GHz Applications

A fully packaged traveling wave photodetector (TWPD) with monolithically integrated optical power splitter for high-speed high-power applications in excess of 100 GHz is demonstrated. The detector module provides a responsivity of 0.24 A/W with a polarization dependence of only 0.2 dB at 1.55 mum wavelength and is suitable for the detection of RZ data rates in excess of 80 Gbit/s with unsaturated peak voltages of >0.5 V. Chip-based measurements show a broadband impedance match, a 3 dB bandwidth of 80 GHz and a maximum electrical output power of -2.5 dBm at 150 GHz.