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arXiv · 0910.0019

Localised Magneto-Optical Collective Excitations of Impure Graphene

A. M. Fischer·A. B. Dzyubenko·R. A. Roemer
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Abstract

We study optically-induced collective excitations of graphene in the presence of a strong perpendicular magnetic field and a single impurity. We determine the energies and absorption strengths of these excitations, which become localised on the impurity. Two different types of impurity are considered i. the long-range Coulomb impurity, ii. a delta-function impurity located at either an A or B graphene sublattice site. Both impurity types result in some bound states appearing both above and below the magnetoplasmon continuum, although the effect of the short-range impurity is less pronounced. The dependence of the energies and oscillator strengths of the bound states on the filling factor is investigated.

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A. M. Fischer, A. B. Dzyubenko, R. A. Roemer. 2009-09-30. Localised Magneto-Optical Collective Excitations of Impure Graphene. https://doi.org/10.1002/andp.200910381

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