Performance of broad-band microwave-biased extrinsic photoconductive detectors at 10.6 µ

An analysis of the photoconductive gain-bandwidth product and SNR is presented, which allows a comparison of microwave-biased and dc-biased extrinsic detectors. The results of an experimental comparison using mercury-doped germanium at 10.6 μ are described. For equal bandwidth of 70 MHz, the measured gain and detectivity were better by a factor of 35 for microwave biasing compared to dc biasing.