Resonance detection of terahertz radiation in submicrometer field-effect GaAs/AlGaAs transistors with two-dimensional electron gas

Resonance detection of terahertz radiation by submicrometer field-effect GaAs/AlGaAs transistors (with the gate length $L$ = 250 nm) with two-dimensional electron gas in the channel has been studied at $T$ = 4.2 K. For these transistors, it is shown for the first time that the maximum of the response (the drain-source photovoltage) shifts with an increasing frequency to the region of higher gate voltages in accordance with the Dyakonov–Shur theory. It is shown that, as temperature is increased to 77 K, the dependence of the photovoltage on the gate voltage becomes nonresonant, which is caused by a decrease in the mobility.