Year: 2012
Type: article
Abstract: We study transport in Weyl semimetals with $N$ isotropic Weyl nodes in the presence of Coulomb interactions or disorder at temperature $T$. In the interacting clean limit, we determine the conductivity $\ensuremath{\sigma}(\ensuremath{\omega},T)$ by solving a quantum Boltzmann equation within a ``leading log'' approximation and find it to be proportional to $T$, up to logarithmic factors arising from the flow of couplings. In the noninteracting disordered case, we compute the Kubo conductivity and show that it behaves differently for $\ensuremath{\omega}\ensuremath{\ll}T$ and $\ensuremath{\omega}\ensuremath{\gg}T$: in the former regime we recover a previous result, of a finite dc conductivity and a Drude width vanishing as $N{T}^{2}$; in the latter, we find that $\ensuremath{\sigma}(\ensuremath{\omega},T)$ vanishes linearly with $\ensuremath{\omega}$ with a leading term as $T\ensuremath{\rightarrow}0$ equal to the clean, free-fermion result: ${\ensuremath{\sigma}}_{0}^{(N)}(\ensuremath{\omega},T=0)=N\frac{{e}^{2}}{12h}\frac{|\ensuremath{\omega}|}{{v}_{F}}$. We compare our results to transport data on ${\mathrm{Y}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$ and comment on the possible relevance to recent experiments on ${\mathrm{Eu}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$.
Source: Physical Review Letters
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: U.S. Department of Energy
OpenAlex ID: W1967379174