Ultrafast two-dimensional electron gas detector and mixer for terahertz radiation

A hot-electron bolometric detector and mixer (heterodyne detector), which uses the nonlinearities of the heated two-dimensional electron gas medium, is proposed and analyzed. The cooling process of the detector is through diffusion of the electrons into the contacts; a time constant of 1 ps and responsivity of 3000 V/W are calculated for a device which is 0.8 μm long. The predicted double-sideband receiver noise temperature for the mixer version is in the range 1000–2000 K at 1 THz, with a 100 GHz intermediate frequency bandwidth. The operating temperature would be 77 K and the local oscillator power 1 μW.