Resonant detection of subterahertz and terahertz radiation by plasma waves in submicron field-effect transistors

TLDR

The study investigates resonant photoresponse of a gated two‑dimensional electron gas to terahertz radiation. Visible‑light illumination increases carrier density and mobility, shifting the resonance to higher gate voltages, improving the quality factor, and enabling resonant detection of Gunn‑diode harmonics up to 1.2 THz, thereby confirming plasma‑wave detection theory.

Abstract

We report on the experiments on resonant photoresponse of the gated two-dimensional electron gas to the terahertz radiation. The visible-light-induced, metastable increase of the carrier density in the transistor channel shifts the resonance position to the higher gate voltages, in agreement with plasma wave detection theory. In this way, an unambiguous proof of the origin of the observed resonant detection is provided. The visible light illumination also leads to an increase of the electron mobility and, as a result, to an increase of the resonant detection quality factor. Resonant detection of the harmonics of the Gunn diode-based emission system is demonstrated up to 1.2 THz.