InP double heterojunction bipolar transistor as sub-terahertz detector

We report on room-temperature detection of sub-terahertz radiation by InP double heterojunction bipolar transistors designed for 100 Gbit/s circuit applications. Maximum responsivity of 250 V/W around 272 GHz were achieved at room-temperature under unbiased base-emitter and base-collector conditions. We show also that these detectors can operate as sensitive broadband THz detectors in THz imaging systems.