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arXiv · 1107.5653

Excitons in Graphene and the Influence of the Dielectric Environment

J. H. Grönqvist·T. Stroucken·G. Berghäuser·S. W. Koch
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Abstract

The exciton Wannier equation for graphene is solved for different background dielectric constants. It is shown that freestanding graphene features strong Coulomb effects with a very large exciton binding energy exceeding $3\,$eV. A second-order transition to a weak Coulomb regime is found if the effective background dielectric constant exceeds a critical value. All bound-state solutions vanish for epitaxial graphene on a substrate with large background permittivity, such as SiC.

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J. H. Grönqvist, T. Stroucken, G. Berghäuser, S. W. Koch. 2011-07-28. Excitons in Graphene and the Influence of the Dielectric Environment. https://arxiv.org/abs/1107.5653

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