Artificial electric field in Fermi Liquids

TL;DR

This paper derives an effective Boltzmann equation for Fermi liquids using Keldysh formalism, revealing an artificial electric field in electron dynamics related to Berry curvature, and proposes a method to detect it via ARPES.

Contribution

It introduces a many-body derivation of Berry curvatures in Fermi liquids, including an artificial electric field, extending non-interacting models to interacting systems.

Findings

Artificial electric field affects Fermi liquid properties.

Explicit impact on renormalization factor and transverse conductivity.

Proposes ARPES method for Berry curvature detection.

Abstract

Based on the Keldysh formalism, we derive an effective Boltzmann equation for a quasi-particle associated with a particular Fermi surface in an interacting Fermi liquid. This provides a many-body derivation of Berry curvatures in electron dynamics with spin-orbit coupling, which has received much attention in recent years in non-interacting models. As is well-known, the Berry curvature in momentum space modifies naive band dynamics via an artificial magnetic field in momentum space. Our Fermi liquid formulation completes the reinvention of modified band dynamics by introducing in addition an "artificial electric field", related to Berry curvature in frequency and momentum space. We show explicitly how the artificial electric field affects the renormalization factor and transverse conductivity of interacting U(1) Fermi liquids with non-degenerate bands. Accordingly, we also propose a method of momentum resolved Berry's curvature detection in terms of angle resolved photoemission spectroscopy (ARPES).