Quantum Size Effects in the Terahertz Nonlinear Response of Metallic Armchair Graphene Nanoribbons

TL;DR

This paper investigates how quantum size effects influence the nonlinear terahertz response of finite-length metallic graphene armchair nanoribbons, revealing conditions that can enhance nonlinearity compared to infinite ribbons.

Contribution

It introduces a time-dependent perturbation theory approach to analyze quantum size effects on the nonlinear response of finite graphene nanoribbons.

Findings

Quantum size effects significantly alter the nonlinear conductance.

Finite-length nanoribbons can exhibit enhanced nonlinearity.

Spectrum broadening impacts the nonlinear response.

Abstract

We use time dependent perturbation theory to study quantum size effects on the terahertz nonlinear response of metallic graphene armchair nanoribbons of finite length under an applied electric field. Our work shows that quantization due to the finite length of the nanoribbon, the applied field profile, and the broadening of the graphene spectrum all play a significant role in the resulting nonlinear conductances. In certain cases, these effects can significantly enhance the nonlinearity over that for infinitely-long metallic armchair graphene nanoribbon.