Plasmonic Helicity-Driven Detector of terahertz radiation

TL;DR

This paper presents a theoretical study of a plasmonic detector that uses helicity-driven nonlinear responses of a 2D electron gas to terahertz radiation, highlighting resonance-enhanced sensitivity for spectrometry.

Contribution

It introduces a new theoretical model describing helicity-sensitive nonlinear responses near plasmonic resonances in 2D electron gases for terahertz detection.

Findings

Helicity-sensitive response peaks near plasmonic resonances.

Response oscillates with phase shift between source and drain signals.

Resonance line shape is asymmetric with frequency deviation.

Abstract

We develop a theory of the helicity driven nolinear dc response of gated two-dimensional electron gas to the terahertz radiation. We demonstrate that the helicity-sensitive part of the response dramatically increases in the vicinity of the plasmonic resonances and oscillates with the phase shift between excitation signals on the source and drain. The resonance line shape is an asymmetric function of the frequency deviation from the resonance. In contrast, the helicity-insensitive part of the response is symmetrical. These properties yield significant advantage for using plasmonic detectors as terahertz and far infrared spectrometers and interferometers.