Building a universal description of certain non-Fermi liquid metals
Numerous strongly correlated materials display non-Fermi liquid properties over a broad range of temperatures. One of the remarkable features observed in many of these systems is the apparent universality of the phenomenology, in spite of the completely distinct microscopic details. Inspired by the rich phenomenology of such non-Fermi liquids, I will construct examples of translationally invariant solvable models of metals, that display crossovers as a function of temperature into regimes with local quantum criticality and non-Fermi liquid behavior. I will show the existence of sharply defined critical Fermi surfaces in the non-Fermi liquid regime, that give rise to quantum oscillations in the magnetization as a function of an external magnetic field, in the absence of quasiparticle excitations. I will discuss the implications of these results for fundamental bounds on relaxation rates and speculate on possible coarse grained descriptions of a class of intermediate scale non-Fermi liquid behavior in generic correlated metals. Finally, if time permits, I will present new experimental results on some unconventional transport properties of magic-angle twisted bilayer graphene and comment on their possible connection with the rest of my talk.
Host: Victor Galitski