Authors: Igor F. Herbut, Vieri Mastropietro

Title: Universal conductivity of graphene in the ultra-relativistic regime
 
Abstract: We calculate the zero temperature dc conductivity in graphene in the ultimate low-energy regime, ects of the electromagnetic interaction become important and when the full Lorentz symmetry emerges. In contrast to what happens with the short range or with the Coulomb long-range instantaneous interactions, the dc conductivity is now no longer equal to its non interacting value, but acquires universal corrections in powers of the ne structure constant. The coefficient of the first order correction is computed, and found to be of order one. We also present the result for the conductivity in the large-N limit, with N as the number of Dirac fermions species, to the order 1/N^2.

Keywords: graphene, retarded Coulomb interactions, conductivity, optical regime, universality, renormalization group

Igor F. Herbut
Department of Physics
Simon Fraser University
Burnaby, British Columbia, Canada V5A 1S6
e-mail: iherbut AT sfu DOT ca

Vieri Mastropietro
Dipartimento di Matematica
Università di Milano
Via Saldini, 50, I-20133 Milano - ITALY
e-mail: Vieri DOT Mastropietro AT unimi DOT it