Vertex renormalization in dc conductivity of doped chiral graphene

TL;DR

This paper provides a quantum derivation of dc conductivity in doped chiral graphene, showing that the semiclassical Boltzmann approach remains valid at large chemical potentials despite graphene's unique chiral properties.

Contribution

It offers a detailed quantum calculation of vertex corrections in graphene's conductivity, clarifying the applicability of semiclassical methods in the presence of chirality.

Findings

Boltzmann approach justified at large chemical potential

Vertex corrections explicitly computed using Kubo formalism

Chirality effects are robust against small sublattice asymmetry

Abstract

The remarkable transport properties of graphene follow not only from the the Dirac-like energy dispersion, but also from the chiral nature of its excitations, which makes unclear the limits of applicability of the standard semiclassical Boltzmann approach. In this paper we provide a quantum derivation of the transport scattering time in graphene in the case of electron-phonon interaction. By using the Kubo formalism, we compute explicitly the vertex corrections to the dc conductivity by retaining the full chiral matrix structure of graphene. We show that at least in the regime of large chemical potential the Boltzmann picture is justified, and it is also robust against a small sublattice inequivalence which partly spoils the role of chirality.