Stokes flow in an electronic fluid with odd viscosity

Abstract

We investigate the transition between elastic and viscous regimes for time-reversal broken Weyl semimetals. In these materials, Hall transport occurs through two parallel channels: the Fermi sea and the Fermi surface. The Fermi sea part remains unaffected by electron-electron scattering, whereas the Fermi surface is influenced by it. We model the disorder by dilute impenetrable spherical impurities. We analyze the flow of an electronic fluid with a finite odd viscosity in the presence of such disorder and compute the conductivity tensor. We find that in the generic case of finite intrinsic conductivity, the Hall angle in the viscous regime is parametrically suppressed compared to the elastic regime. In the special case where the intrinsic conductivity vanishes, the ratio between the transverse and the longitudinal resistivities matches the ratio between the odd and even components of the viscosity tensor.