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arXiv · 0706.2185

Electron-Electron Interactions in the Vacuum Polarization of Graphene

Valeri N. Kotov·Bruno Uchoa·A. H. Castro Neto
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Abstract

We discuss the effect of electron-electron interactions on the static polarization properties of graphene beyond RPA. Divergent self-energy corrections are naturally absorbed into the renormalized coupling constant $α$. We find that the lowest order vertex correction, which is the first non-trivial correlation contribution, is finite, and about 30% of the RPA result at strong coupling $α\sim 1$. The vertex correction leads to further reduction of the effective charge. Finite contributions to dielectric screening are expected in all orders of perturbation theory.

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Valeri N. Kotov, Bruno Uchoa, A. H. Castro Neto. 2008-06-04. Electron-Electron Interactions in the Vacuum Polarization of Graphene. https://doi.org/10.1103/physrevb.78.035119

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