25-Gb/s 1310-nm optical receiver based on a Sub-5-V waveguide-coupled Germanium avalanche photodiode

摘要

We demonstrate low-voltage waveguide-coupled germanium avalanche photodetectors (APDs) with a (wafer-scale mean) gain x bandwidth product of 140 GHz at -5 V by utilizing a 185-nm-thick Ge layer. An optical receiver based on such an APD operating up to 25 Gb/s is demonstrated.