Space-Charge Effect Assisted GeSi Avalanche Photodetector with Record 67 GHz Bandwidth

A high-bandwidth Ge/Si waveguide avalanche photodetector is experimentally demonstrated. The presented device has a moderate gain of 12.3 and a record-high bandwidth of 67 GHz assisted by the prominent space-charge effect under high reverse voltage. This high-bandwidth avalanche photodetector shows great potential for high-sensitivity detection in the single lane 100G/200G receiving.