Condensed Matter Seminars

Linear temperature dependence of transport coefficients in metals is habitually ascribed to non-Fermi-liquid physics. In this talk we establish this behavior for 2D electron fluids, systems in which carrier collisions assist conduction, leading to resistance decreasing with temperature. As we will see, electron fluids with simple Fermi surfaces obey nonclassical hydrodynamics described by a loop representing the Fermi surface shape evolving in space and time. Replacing the fluid velocity dynamics with an amoeba-like loop dynamics leads to a large family of long-lived excitations manifest as multiple viscous modes. A cascade of these modes results in a linear T dependence that extends down to lowest temperatures, as well as a Kolmogorov-like fractional power -5/3 scaling of conductivity vs. wavenumber. These dependences provide a smoking gun for nonclassical hydrodynamics and are expected to be generic for strongly-correlated 2D systems with near-circular Fermi surfaces.