An array of integrated on a chip GaAs/InGaAs/AlGaAs-field-effect transistors with floating electrodes for detection of terahertz radiation

An array of GaAs/InGaAs/AlGaAs field-effect transistors with an asymmetric T-gate in each transistor and floating electrodes was fabricated on a single chip and tested as a detector of terahertz (THz) radiation. Principle of detection was based on excitation of plasma oscillations in the common electron channel of the FETs array. Strong terahertz photovoltaic response was demonstrated without any supplementary antenna. Voltage re-sponsivities above 1000 V/W and up to 2000 V/W were obtained at zero (unbiased mode) and positive (directed from drain to source — biased mode) dc currents in the FETs array channel, respectively, surpassing the photorespponse demonstrated by the array of FETs connected in series by external wiring [5].