Non-trivial Infrared Structure in (2+1)-dimensional Quantum Electrodynamics

TL;DR

This paper demonstrates that in (2+1)-dimensional quantum electrodynamics with multiple flavors, gauge-fermion interactions lead to non-Fermi liquid behavior characterized by a non-trivial fixed point and slowed coupling flow, confirmed through Schwinger-Dyson analysis.

Contribution

It provides a leading-1/N resummed analysis showing non-trivial infrared fixed points and deviations from Fermi-liquid theory in multiflavour (2+1)D QED with a finite infrared cutoff.

Findings

Existence of a non-trivial fixed point at zero momentum.

Significant slowing of the running coupling at intermediate scales.

Deviations from traditional Fermi-liquid behavior.

Abstract

We show that the gauge-fermion interaction in multiflavour $(2+1)$-dimensional quantum electrodynamics with a finite infrared cut-off is responsible for non-fermi liquid behaviour in the infrared, in the sense of leading to the existence of a non-trivial fixed point at zero momentum, as well as to a significant slowing down of the running of the coupling at intermediate scales as compared with previous analyses on the subject. Both these features constitute deviations from fermi-liquid theory. Our discussion is based on the leading- $1/N$ resummed solution for the wave-function renormalization of the Schwinger-Dyson equations . The present work completes and confirms the expectations of an earlier work by two of the authors (I.J.R.A. and N.E.M.) on the non-trivial infrared structure of the theory.