Marginal Fermi liquid behavior from 2d Coulomb interaction

TL;DR

This paper uses a nonperturbative renormalization group approach to analyze how Coulomb interactions in a 2D graphite layer lead to marginal Fermi liquid behavior, explaining deviations from traditional Fermi liquid theory.

Contribution

It provides a nonperturbative analysis showing Coulomb interactions induce marginal Fermi liquid behavior in 2D graphite, with implications for understanding quasiparticle decay rates.

Findings

Model flows towards noninteracting fixed point with logarithmic corrections.

Coulomb interactions are marginal, causing deviations from Fermi liquid behavior.

Results explain experimental observations of linear quasiparticle decay in graphite.

Abstract

A full, nonperturbative renormalization group analysis of interacting electrons in a graphite layer is performed, in order to investigate the deviations from Fermi liquid theory that have been observed in the experimental measures of a linear quasiparticle decay rate in graphite. The electrons are coupled through Coulomb interactions, which remain unscreened due to the semimetallic character of the layer. We show that the model flows towards the noninteracting fixed-point for the whole range of couplings, with logarithmic corrections which signal the marginal character of the interaction separating Fermi liquid and non-Fermi liquid regimes.