Many-body corrections to cyclotron resonance in graphene

We report our recent study of cyclotron resonance in graphene, with focus on the many-body effect on the resonance energies. The genuine many-body corrections turn out to derive from vacuum polarization, specific to graphene, which diverges at short wavelengths and which requires renormalization of velocity and, for bilayer graphene, interlayer coupling as well. As a result, the renormalized velocity and interlayer coupling strength run with the magnetic field, and many-body corrections are uniquely determined from one resonance to another. Theory is compared with the experimental data for both monolayer and bilayer graphene.