Gauge invariant response functions in Algebraic Fermi liquids

TL;DR

This paper introduces a new method for calculating response functions in gauge-coupled fermion systems, applied to the Algebraic Fermi liquid model relevant for cuprate superconductors, revealing anomalous dimensions and symmetry-consistent behavior.

Contribution

A novel method for evaluating two-loop response functions in gauge-coupled fermion systems, applied to the Algebraic Fermi liquid in cuprate superconductors.

Findings

Staggered spin susceptibility exhibits an anomalous dimension .

Other correlators align with conservation laws and symmetries.

Method simplifies complex two-loop response function calculations.

Abstract

A new method is developed that permits the simple evaluation of two-loop response functions for fermions coupled to a gauge field. We employ this method to study the gauge-invariant response functions in the Algebraic Fermi liquid, a non-Fermi liquid state proposed to describe the pseudogap phase in the QED3 theory of cuprate superconductors. The staggered spin susceptibility is found to exhibit a characteristic anomalous dimension exponent \eta_4, while other correlators show behavior consistent with the conservation laws imposed by the symmetries of the underlying theory.