An Antenna-Coupled Dual-Gated Electron Channel as Direct Detector of 2 THz Radiation

An antenna-coupled dual-gated two-dimensional electron gas (2DEG) based on a GaAs-AlGaAs heterostructure shows a pronounced response to 2 THz radiation. The device is shown to be a direct detector, and its photoresponse arises without any source-drain bias. The detection is based on a novel mechanism that yields a substantially stronger photoresponse than predicted by the classical plasma-wave self-mixing and other mechanisms.