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arXiv · 1305.1448

Collisionless Hydrodynamics of Doped Graphene in a Magnetic Field

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

The electrodynamics of a two-dimensional gas of massless fermions in graphene is studied by a collisionless hydrodynamic approach. A low-energy dispersion relation for the collective modes (plasmons) is derived both in the absence and in the presence of a perpendicular magnetic field. The results for graphene are compared to those for a standard two-dimensional gas of massive electrons. We further compare the results within the classical hydrodynamic approach to the full quantum mechanical calculation in the random phase approximation. The low-energy dispersion relation is shown to be a good approximation at small wave vectors. The limitations of this approach at higher order is also discussed.

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R. Roldán, J. -N. Fuchs, M. O. Goerbig. 2013-05-07. Collisionless Hydrodynamics of Doped Graphene in a Magnetic Field. https://doi.org/10.1016/j.ssc.2013.04.011

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