Geometric universality of plasmon modes in graphene nanoribbon arrays

TL;DR

This paper reveals the geometric universality of plasmon modes in graphene nanoribbon arrays, providing universal parameters and an analytical model to understand their optical response, aiding experimental analysis.

Contribution

It demonstrates the purely geometric nature of size quantization for graphene plasmons and provides universal parameters and an analytical theory for their optical response.

Findings

Universal geometric parameters for plasmon size quantization

Analytical theory reproduces qualitative features of plasmon response

Numerical calculations support the geometric universality

Abstract

Graphene plasmonics is a rapidly growing field with multiple potential applications. One of the standard ways to study plasmons in graphene is by fabricating an array of graphene nanoribbons where nanoribbon edges provide the efficient photon-plasmon coupling. We systematically analyze the problem of optical plasmonic response in such systems and demonstrate the purely geometric nature of the size quantization condition for graphene plasmons. Accurate numerical calculations allowed us to tabulate the universal geometric parameters of plasmon size quantization, which is expected to become useful in analysis of experimental data on plasmonic response of graphene nanoribbons. A simple analytical theory has also been developed which accurately reproduces all the qualitative features of optical plasmonic response of graphene nanoribbons.