Schrodinger Fermi Liquids

TL;DR

This paper explores a holographic model of strongly interacting fermionic systems in 2+1D, revealing a quantum phase transition between Fermi-liquid and non-Fermi-liquid states driven by background density, with implications for understanding Fermi surface disappearance.

Contribution

It introduces a holographic dual description of Schrodinger Fermi liquids, demonstrating a quantum phase transition characterized by changes in spectral function and quasiparticle dispersion.

Findings

Identification of a sharp quasiparticle pole indicating a Fermi surface at high density

Disappearance of the Fermi surface and hump in spectral function at low density

Transition from Fermi-liquid-like to non-Fermi-liquid scaling of quasiparticle dispersion

Abstract

A class of strongly interacting many-body fermionic systems in 2+1D non-relativistic conformal field theory is examined via the gauge-gravity duality correspondence. The 5D charged black hole with asymptotic Schrodinger isometry in the bulk gravity side introduces parameters of background density and finite particle number into the boundary field theory. We propose the holographic dictionary, and realize a quantum phase transition of this fermionic liquid with fixed particle number by tuning the background density $\beta$ at zero temperature. On the larger $\beta$ side, we find the signal of a sharp quasiparticle pole on the spectral function A(k,w), indicating a well-defined Fermi surface. On the smaller $\beta$ side, we find only a hump with no sharp peak for A(k,w), indicating the disappearance of Fermi surface. The dynamical exponent $z$ of quasiparticle dispersion goes from being Fermi-liquid-like $z\simeq1$ scaling at larger $\beta$ to a non-Fermi-liquid scaling $z\simeq 3/2$ at smaller $\beta$. By comparing the structure of Green's function with Landau Fermi liquid theory and Senthil's scaling ansatz, we further investigate the behavior of this quantum phase transition.