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arXiv · 0802.4289

Quantum critical transport in clean graphene

Lars Fritz·Joerg Schmalian·Markus Mueller·Subir Sachdev
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Abstract

We describe electrical transport in ideal single-layer graphene at zero applied bias. There is a crossover from collisionless transport at frequencies larger than k_B T/hbar (T is the temperature) to collision-dominated transport at lower frequencies. The d.c. conductivity is computed by the solution of a quantum Boltzmann equation. Due to a logarithmic singularity in the collinear scattering amplitude (a consequence of relativistic dispersion in two dimensions) quasi-particles and -holes moving in the same direction tend to an effective equilibrium distribution whose parameters depend on the direction of motion. This property allows us to find the non-equilibrium distribution functions and the quantum critical conductivity exactly to leading order in 1/|ln(alpha)| where alpha is the coupling constant characterizing the Coulomb interactions.

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Lars Fritz, Joerg Schmalian, Markus Mueller, Subir Sachdev. 2008-03-09. Quantum critical transport in clean graphene. https://doi.org/10.1103/physrevb.78.085416

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