Terahertz detection in a slit-grating-gate field-effect-transistor structure

TL;DR

This paper reports on a novel slit-grating-gate FET structure that significantly enhances terahertz detection sensitivity by exploiting plasmon resonances, achieving responsivity two orders of magnitude higher than previous detectors.

Contribution

The paper introduces a new slit-grating-gate FET design that greatly improves terahertz responsivity through enhanced plasmon coupling.

Findings

Resonant peaks correspond to plasmon excitations.

Responsivity exceeds previous detectors by 100 times.

Enhanced coupling boosts terahertz detection efficiency.

Abstract

We have fabricated a grating-gate InGaAs/GaAs field-effect transistor structure with narrow slits between the grating gate fingers. The resonant photoconductive response of this structure has been measured in the sub-terahertz frequency range. The frequencies of the photoresponse peaks correspond to the excitation of the plasmon resonances in the structure channel. The obtained responsivity exceeds the responsivity reported previously for similar plasmonic terahertz detectors by two orders of magnitude due to enhanced coupling between incoming terahertz radiation and plasmon oscillations in the slit-grating-gate field-effect transistor structure.