Large N theory of critical Fermi surfaces II: conductivity

ORAL

Abstract

A Fermi surface coupled to a scalar field can be described in a 1/N expansion by choosing the fermionscalar Yukawa coupling to be random in the N-dimensional flavor space, but invariant under translations. We compute the conductivity of such a theory in two spatial dimensions for a critical scalar. We find a Drude contribution, and verify that the proposed 1/ω2/3 contribution to the optical conductivity at frequency ω has vanishing co-efficient for a convex Fermi surface. We also describe the influence of impurity scattering of the fermions, and find that while the self energy resembles a marginal Fermi liquid, the resistivity and optical conductivity behave like a Fermi liquid.

*This research was supported by the National Science Foundation under Grant No. DMR-2002850. I. E. acknowledges support from the Harvard Quantum Initiative Postdoctoral Fellowship in Science and Engineering. This work was also supported by the Simons Collaboration on Ultra-Quantum Matter, which is a grant from the Simons Foundation (651440, S.S.). This research was supported in part by the Heising-Simons Foundation, the Simons Foundation, and National Science Foundation Grant No. NSF PHY-1748958. The Flatiron Institute is a division of the Simons Foundation.

Publication: Phys. Rev. B 106, 115151

Presenters

  • Haoyu Guo

    • Harvard University

Authors

  • Haoyu Guo

    • Harvard University
  • Aavishkar A Patel

    • Center for Computational Quantum Physics, Flatiron Institute
    • Flatiron Institute
    • Flatiron Institute, Simons Foundation
  • Ilya Esterlis

    • Harvard University
  • Subir Sachdev

    • Harvard University