2008/05/31 by Markus Mueller, Markus Müller, Lars Fritz +1
Materials Science · Physics and Astronomy · #Boltzmann constant #Condensed matter physics #Coulomb #Crossover #Dirac fermion #Electron #Fermi liquid theory #Fermion #Graphene research and applications #Magnetic field #Magnetoresistance #Physics #Quantum and electron transport phenomena #Quantum mechanics #Topological Materials and Phenomena #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.115406
published as Phys. Rev. B 78, 115406 (2008)
arxiv created 2008/09/05 · openalex publication_date 2008/09/05 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study the thermal and electric transport of a fluid of interacting Dirac fermions using a Boltzmann approach. 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 \ensuremathμ. In the quantum-critical regime \ensuremathμ\ensuremath\lesssimT we find pronounced deviations from Fermi-liquid behavior, such as a collective cyclotron resonance with an intrinsic collision-broadened width and significant enhancements of the Mott and Wiedemann-Franz ratios. Some of these results have been anticipated by a relativistic hydrodynamic theory, whose precise range of validity and failure at large fields and frequencies we determine. The Boltzmann approach allows us to go beyond the hydrodynamic regime and to quantitatively describe the deviations from magnetohydrodynamics and 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. Finally, we obtain the full frequency and doping dependence of the single universal conductivity \ensuremathσQ which parametrizes the hydrodynamic response.