Relativistic magnetotransport in graphene

TL;DR

This paper investigates the thermal and electric transport properties of interacting Dirac fermions in graphene under magnetic fields, revealing universal behavior, collective resonances, and crossovers between different transport regimes.

Contribution

It provides a microscopic derivation of relativistic magnetohydrodynamics for graphene's transport and explores the crossover between collision-dominated, disorder-dominated, and ballistic regimes.

Findings

Universal, collision-dominated transport coefficients in the critical regime.

Observation of a collective cyclotron resonance.

Crossover behavior from Fermi liquid to relativistic hydrodynamics.

Abstract

We study the thermal and electric transport of a fluid of interacting Dirac fermions as they arise in single-layer graphene. We include Coulomb interactions, a dilute density of charged impurities and the presence of a magnetic field to describe both the static and the low frequency response as a function of temperature T and chemical potential mu. In the critical regime mu << T where both bands above and below the Dirac point contribute to transport we find pronounced deviations from Fermi liquid behavior, universal, collision-dominated values for transport coefficients and a cyclotron resonance of collective nature. In the collision-dominated high temperature regime the linear thermoelectric transport coefficients are shown to obey the constraints of relativistic magnetohydrodynamics which we derive microscopically from Boltzmann theory. The latter also allows us to describe the crossover to disorder-dominated Fermi liquid behavior at large doping and low temperatures, as well as the crossover to the ballistic regime at high fields.