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arXiv · 1802.09898

Field theoretic renormalization study of interaction corrections to the universal ac conductivity of graphene

S. Teber·A. V. Kotikov
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Abstract

The two-loop interaction correction coefficient to the universal ac conductivity of disorder-free intrinsic graphene is computed with the help of a field theoretic renormalization study using the BPHZ prescription. Non-standard Ward identities imply that divergent subgraphs (related to Fermi velocity renormalization) contribute to the renormalized optical conductivity. Proceeding either via density-density or via current-current correlation functions, a single well-defined value is obtained: $\mathcal{C}= (19-6\pi)/12) = 0.01$ in agreement with the result first obtained by Mishchenko and which is compatible with experimental uncertainties.

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S. Teber, A. V. Kotikov. 2018-02-27. Field theoretic renormalization study of interaction corrections to the universal ac conductivity of graphene. https://doi.org/10.1007/jhep07(2018)082

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