Terahertz Generation and Amplification in Graphene Nanoribbons in Multi-frequency Electric Fields

TL;DR

This paper theoretically investigates how graphene nanoribbons can generate and amplify terahertz radiation using multi-frequency electric fields, highlighting two main schemes based on frequency relationships.

Contribution

It introduces novel schemes for terahertz generation and amplification in graphene nanoribbons driven by multi-frequency fields, expanding potential nanoelectronic applications.

Findings

THz generation via wave mixing when frequencies are commensurate

Suppression of space charge instability with strong fields in non-commensurate cases

Graphene as a promising substitute for semiconductor nanoelectronic devices

Abstract

We study theoretically a multi-frequency response of electrons in confined graphene subject to dc-ac driven fields. We explore the possibility for using graphene nanoribbons (GNRs) to generate and amplify terahertz (THz) radiations in electric field domainless regime. We discover two main important schemes of generation; when the frequencies are commensurate, THz generation is due to wave mixing and when they are non-commensurate, a single strong field suppresses space charge instability and any weak signals can get amplified. The use of graphene as a best substitute for semiconductor nanoelectronic devices is suggested.