High-Power High-Speed Photodetectors—Design, Analysis, and Experimental Demonstration

Abstract—A novel velocity-matched distributed photodetector (VMDP) is proposed to simultaneously achieve high saturation photocurrent and broad bandwidth. Theoretical analysis on the tradeoff between saturation power and bandwidth shows that the VMDP offers fundamental advantages over conventional photodetectors. A comprehensive theoretical model has been developed for the design and simulation of the VMDP. Experi-mentally, the VMDP with very high saturation (56-mA) photocur-rent and instrument-limited 3-dB bandwidth (49 GHz) has been demonstrated. The theoretical analysis and experimental results show that the VMDP is very attractive for high-performance microwave photonic links and high-power optical microwave applications. Index Terms — Coplanar transmission lines, millimeter-wave generation, MSM photodiodes, nonlinearities, photodetectors, op