Many-body corrections to cyclotron resonance in monolayer and bilayer graphene

TL;DR

This paper investigates many-body effects on cyclotron resonance in monolayer and bilayer graphene, highlighting the role of vacuum polarization and the necessity of renormalization to match experimental observations.

Contribution

It introduces a renormalization approach to account for many-body corrections in graphene's cyclotron resonance, including the effects of vacuum polarization and coupling strength renormalization.

Findings

Many-body corrections derive from vacuum polarization effects.

Renormalization allows unique determination of corrections from resonance data.

Velocity and interlayer coupling in bilayer graphene run with magnetic field.

Abstract

Cyclotron resonance in graphene is studied with focus on many-body corrections to the resonance energies, which evade Kohn's theorem. The genuine many-body corrections turn out to derive from vacuum polarization, specific to graphene, which diverges at short wavelengths. Special emphasis is placed on the need for renormalization, which allows one to determine many-body corrections uniquely from one resonance to another. For bilayer graphene, in particular, both intralayer and interlayer coupling strengths undergo infinite renormalization; as a result, the renormalized velocity and interlayer coupling strength run with the magnetic field. A comparison of theory with the experimental data is made for both monolayer and bilayer graphene.