Theory of the plasma-wave photoresponse of a gated graphene sheet

TL;DR

This paper develops an analytical theory for the photoresponse of gated graphene, showing how plasma wave excitation leads to photodetection, influenced by graphene's unique relativistic carrier dynamics, with potential efficiency improvements.

Contribution

It introduces a fully analytical plasma-wave-based photoresponse theory for graphene, highlighting the impact of relativistic Dirac fermions on photodetection efficiency.

Findings

Plasma wave excitation significantly contributes to graphene's photoresponse.

Relativistic hydrodynamics reveals enhanced photodetection efficiency in graphene.

The theory predicts improved performance over traditional semiconductor structures.

Abstract

The photoresponse of graphene has recently received considerable attention. The main mechanisms yielding a finite dc response to an oscillating radiation field which have been investigated include responses of photovoltaic, photo-thermoelectric, and bolometric origin. In this Article we present a fully analytical theory of a photoresponse mechanism which is based on the excitation of plasma waves in a gated graphene sheet. By employing the theory of relativistic hydrodynamics, we demonstrate that plasma-wave photodetection is substantially influenced by the massless Dirac fermion character of carriers in graphene and that the efficiency of photodetection can be improved with respect to that of ordinary parabolic-band electron fluids in semiconductor heterostructures.