Plasmonic terahertz detection by a double-grating-gate field-effect transistor structure with an asymmetric unit cell

TL;DR

This paper theoretically demonstrates that a double-grating-gate FET with an asymmetric unit cell can achieve high responsivity in terahertz detection at room temperature, surpassing previous uncooled detectors without additional antennas.

Contribution

It introduces a novel asymmetric double-grating-gate FET design that significantly enhances terahertz responsivity through intrinsic antenna effects.

Findings

Responsivity exceeds 8 kV/W at room temperature.

Responsivity is an order of magnitude higher than previous detectors.

The structure acts as an effective antenna without external elements.

Abstract

Plasmonic terahertz detection by a double-grating gate field-effect transistor structure with an asymmetric unit cell is studied theoretically. Detection responsivity exceeding 8 kV/W at room temperature in the photovoltaic response mode is predicted for strong asymmetry of the structure unit cell. This value of the responsivity is an order of magnitude greater than reported previously for the other types of uncooled plasmonic terahertz detectors. Such enormous responsivity can be obtained without using any supplementary antenna elements because the double-grating gate acts as an aerial matched antenna that effectively couples the incoming terahertz radiation to plasma oscillations in the structure channel.