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arXiv · 1012.0779

Theory of Bernstein Modes in Graphene

R. Roldan·M. O. Goerbig·J. -N. Fuchs
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Abstract

We present a theoretical description of Bernstein modes that arise as a result of the coupling between plasmon-like collective excitations (upper-hybrid mode) and inter-Landau-level excitations, in graphene in a perpendicular magnetic field. These modes, which are apparent as avoided level crossings in the spectral function obtained in the random-phase approximation, are described to great accuracy in a phenomenological model. Bernstein modes, which may be measured in inelastic light-scattering experiments or in photo-conductivity spectroscopy, are a manifestation of the Coulomb interaction between the electrons and may be used for a high-precision measurement of the upper-hybrid mode at small non-zero wave vectors.

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R. Roldan, M. O. Goerbig, J. -N. Fuchs. 2011-04-23. Theory of Bernstein Modes in Graphene. https://doi.org/10.1103/physrevb.83.205406

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