Features due to spin-orbit coupling in the optical conductivity of single-layer graphene

TL;DR

This paper calculates the optical conductivity of pristine single-layer graphene considering spin-orbit coupling effects, providing analytical insights into how these couplings influence optical properties and suggesting experimental ways to measure them.

Contribution

It introduces analytical results for the optical conductivity of graphene with spin-orbit coupling, distinguishing effects from different types of spin splitting.

Findings

Analytical expressions for optical conductivity with spin-orbit effects

Identification of features due to intrinsic and structural-inversion asymmetry

Proposal to measure spin splitting strengths via optical conductivity

Abstract

We have calculated the optical conductivity of a disorder-free single graphene sheet in the presence of spin-orbit coupling, using the Kubo formalism. Both intrinsic and structural-inversion-asymmetry induced types of spin splitting are considered within a low-energy continuum theory. Analytical results are obtained that allow us to identify distinct features arising from spin-orbit couplings. We point out how optical-conductivity measurements could offer a way to determine the strengths of spin splitting due to various origins in graphene.