Abstract
We report on resonant terahertz detection by the two-dimensional electron plasma in nanometric InGaAs and GaN transistors. Up to now, the majority of research has been devoted to GaAs-based devices as the most promising from the point of view of the electron mobility. However, resonant detection has been reported only in the sub-THz range. According to the predictions of the Dyakonov–Shur plasma wave detection theory, an increase of the detection frequency can be achieved by reducing the length or increasing the carrier density in the gated region. We demonstrate that the 1 THz limit can be overcome by using ultimately short-gate InGaAs and GaN nanotransistors. For the first time the tunability of the resonant signal by the applied gate voltage is demonstrated. We show that the physical mechanism of the detection is related to the plasma waves excited in the transistor channel (Dyakonov–Shur theory). We also show that increasing of the drain-to-source current leads to a transformation of the broadband detection to a resonant and tuneable one. We can get resonant detection at room temperature. We finally discuss the possible application of detection by nanotransistors in different types of THz spectroscopy research.