title: Critical transport in weakly disordered semiconductors and semimetals.
abstract: Motivated by Weyl semimetals and weakly doped semiconductors, we study transport in a weakly disordered semiconductor with a power-law quasiparticle dispersion ξ_{k}∝k^{α}. We show, that in 2α dimensions short-correlated disorder experiences logarithmic renormalization from all energies in the band. We study the case of a general dimension d using a renormalization group, controlled by an ϵ=2α-d expansion. Above the critical dimensions, conduction exhibits a localization-delocalization phase transition or a sharp crossover (depending on the symmetries of the Hamiltonian) as a function of disorder strength. We utilize this analysis to compute the low-temperature conductivity in Weyl semimetals and weakly doped semiconductors near and below the critical disorder point.
authors.affiliation: Physics Department, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: S V
authors.initials: SV
authors.lastname: Syzranov
authors.affiliation: Physics Department, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: L
authors.initials: L
authors.lastname: Radzihovsky
authors.affiliation: Physics Department, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: V
authors.initials: V
authors.lastname: Gurarie