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arXiv · 0909.1682

High-energy excitonic effects in graphite and graphene

Paolo E. Trevisanutto·Markus Holzmann·Michel Cote·Valerio Olevano
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Abstract

We present ab initio many-body calculations of the optical absorption in bulk graphite, graphene and bilayer of graphene. Electron-hole interaction is included solving the Bethe-Salpeter equation on top of a GW quasiparticle electronic structure. For all three systems, we observe strong excitonic effects at high energy, well beyond the continuum of π-> π* transitions. In graphite, these affect the onset of σ-> σ* transitions. In graphene, we predict an excitonic resonance at 8.3 eV arising from a background continuum of dipole forbidden transitions. In the graphene bilayer, the resonance is shifted to 9.6 eV. Our results for graphite are in good agreement with experiments.

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Paolo E. Trevisanutto, Markus Holzmann, Michel Cote, Valerio Olevano. 2010-09-08. High-energy excitonic effects in graphite and graphene. https://doi.org/10.1103/physrevb.81.121405

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