Optical Properties of Strained Graphene

TL;DR

This paper investigates how uniaxial strain affects the optical conductivity and transparency of graphene, revealing strain-dependent optical properties and potential for atomically thin optical devices.

Contribution

It analytically characterizes the strain-induced breakdown of transparency and introduces polarization-based methods to measure strain and lattice orientation in graphene.

Findings

Strain causes measurable changes in graphene's optical transmittance.

Polarization dependence reveals strain magnitude and direction.

Direction-dependent selection rules identify lattice orientation.

Abstract

The optical conductivity of graphene strained uniaxially is studied within the Kubo-Greenwood formalism. Focusing on inter-band absorption, we analyze and quantify the breakdown of universal transparency in the visible region of the spectrum, and analytically characterize the transparency as a function of strain and polarization. Measuring transmittance as a function of incident polarization directly reflects the magnitude and direction of strain. Moreover, direction-dependent selection rules permit identification of the lattice orientation by monitoring the van-Hove transitions. These photoelastic effects in graphene can be explored towards atomically thin, broadband optical elements.