Abstract
Far from resonance, the coupling of the -band phonon to magnetoexcitons in single layer graphene displays kinks and splittings versus filling factor that are well described by Pauli blocking and unblocking of inter- and intra-Landau level transitions. We explore the nonresonant electron-phonon coupling by high-magnetic field Raman scattering while electrostatic tuning of the carrier density controls the filling factor. We show qualitative and quantitative agreement between spectra and a linearized model of electron-phonon interactions in magnetic fields. The splitting is caused by dichroism of left- and right-handed circular polarized light due to lifting of the -band phonon degeneracy, and the piecewise linear slopes are caused by the linear occupancy of sequential Landau levels versus .
- Received 23 July 2013
DOI:https://doi.org/10.1103/PhysRevLett.112.056803
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