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

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 Bogoliubov-Parasiuk-Hepp-Zimmermann prescription. Non-standard Ward identities imply that divergent subgraphs (related to Fermi velocity renormalization) contribute to the renormalized optical conductivity. Proceeding either via densitydensity or via current-current correlation functions, a single well-defined value is obtained: C = (19 − 6π)/12) = 0.01 in agreement with the result first obtained by Mishchenko and which is compatible with experimental uncertainties.

Multi-Loop Techniques for Massless Feynman Diagram Calculations

“…Their accurate study with the help of the methods reviewed in this manuscript could reveal some of their duality [136] and, as a consequence, some relation between the results for these two different models (see [175] for a review). Among other recent achievements of these techniques, let's briefly mention: their application to models with broken-Lorentz invariance [130,131], the calculation of the critical index η of the Φ 3 -model at four-loops [176], the computation of the anomalous dimension of double trace operators in hexagonal fishnet models [177], .... and more to come in the next years.…”