A 1550-NM MILLIMETER-WAVE PHOTODETECTOR WITH A BANDWIDTH-EFFICIENCY PRODUCT OF 2.4 THZ

The monolithic integration of an optical preamplifier and a waveguide p-i-n photodiode has resulted in a 1550-nm photodetector having an external quantum efficiency of 72 (a responsivity of 89 A/W) and an electrical bandwidth of 33.5 GHz. These figures combine to give a bandwidth efficiency product of 2.4 THz, which is approximately one hundred times higher than for any other type of millimeter-wave photodetector published to date. In addition, the preamplifier performance is supplemented by wide optical bandwidth (60 nm), low polarization sensitivity (1 dB), near traveling wave amplification (1-dB maximum gain ripple), and high saturated output power (+11 dBm). The principal advance over work reported earlier is the traveling wave operation of the monolithic optical preamplifier.