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arXiv · 1402.3737

Critical transport in weakly disordered semiconductors and semimetals

S. V. Syzranov·L. Radzihovsky·V. Gurarie
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Abstract

Motivated by Weyl semimetals and weakly doped semiconductors, we study transport in a weakly disordered semiconductor with a power-law quasiparticle dispersion $ξ_{\bf k}\propto k^α$. We show, that in $2α$ dimensions short-correlated disorder experiences logarithmic renormalisation from all energies in the band. We study the case of a general dimension $d$ using a renormalisation group, controlled by an $\varepsilon=2α-d$-expansion. Above the critical dimensions, conduction exhibits a localisation-delocalisation phase transition or a sharp crossover (depending on the symmetries of the Hamiltonian) as a function of disorder strength. We utilise this analysis to compute the low-temperature conductivity in Weyl semimetals and weakly doped semiconductors near and below the critical disorder point.

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S. V. Syzranov, L. Radzihovsky, V. Gurarie. 2015-04-12. Critical transport in weakly disordered semiconductors and semimetals. https://doi.org/10.1103/physrevlett.114.166601

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