Magnetotransport of tomographic electrons in a Corbino disk

Abstract

In clean electron gases at low-to-moderate temperatures, odd-parity modes of the Fermi surface are anomalously long-lived due to Pauli blocking, giving rise to ``tomographic transport'' that is not captured by a hydrodynamic model. Here we show that tomographic flow in a Corbino disk induces an extended boundary layer near electrodes with superballistic transport and enhanced slip velocity, which leads to a parametric enhancement of the quadratic magnetoresistance coefficient. The enhancement depends explicitly on the electrode curvature, allowing its strength to be controlled by the device geometry. The magnetoresistance coefficient reveals three distinct regimes as a function of magnetic field: a tomographic regime at weak fields; a hydrodynamic regime at intermediate fields, reached when the cyclotron radius becomes comparable to a large odd-mode mean free path; and a conventional Ohmic regime at large fields, reached when the cyclotron radius becomes comparable to the short even-mode mean free path. The tomographic regime is characterized by an anomalous dependence of the magnetoresistance on temperature and density, which may account for recent experimentally observed anomalous scaling of the electron viscosity.