Signature of electronic excitations in the Raman spectrum of graphene

Oleksiy Kashuba; Vladimir I. Fal'ko

doi:10.1103/physrevb.80.241404

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arXiv · 0906.5251

Signature of electronic excitations in the Raman spectrum of graphene

Oleksiy Kashuba·Vladimir I. Fal'ko

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Abstract

Inelastic light scattering from Dirac-type electrons in graphene is shown to be dominated by the generation of the inter-band electronic modes which are odd in terms of time-inversion symmetry and belong to the irreducible representation A$_2$ of the point group C$_{6v}$ of the honeycomb crystal. At high magnetic fields, these electron-hole excitations appear as peculiar $n^- \to n^+$ inter-Landau-level modes with energies $ω_n=2\sqrt{2n} \hbar v/λ_B$ and characteristically crossed polarisation of in/out photons.

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Oleksiy Kashuba, Vladimir I. Fal'ko. 2010-01-25. Signature of electronic excitations in the Raman spectrum of graphene. https://doi.org/10.1103/physrevb.80.241404

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