Transport in Weyl Semimetals (original) (raw)

We study transport in three dimensional Weyl semimetals in the presence of Coulomb interactions or disorder. We consider N Weyl nodes with isotropic dispersion at temperature T. In the clean limit, including Coulomb interactions, we determine the conductivity by solving a quantum Boltzmann equation within a 'leading log' approximation. The conductivity is found to be proportional to T , upto logarithmic factors arising from the flow of couplings. In the disordered case, we use the Kubo formula to compute conductivity of non-interacting electrons in the presence of impurities. Here, the finite-frequency conductivity exhibits distinct behaviors, depending on whether ω ≪ T or ω ≫ T : in the former regime we recover the results of a previous analysis, of a finite conductivity and a Drude width that vanishes as N T 2 ; however, in the latter case, we find a conductivity that vanishes linearly with ω whose leading contribution as T → 0 is the same as that of the clean, non-interacting system σ(ω, T = 0) = N e 2 12h |ω| v F. A comparison is made with existing dc transport data in a pyrochlore iridate, which is predicted to have N = 24 Weyl nodes.