Interlayer tunneling in a non-Fermi-liquid metal

TL;DR

This paper investigates how interlayer tunneling affects a gauge theory model of a quasi-two-dimensional metal near magnetic phase transitions, revealing suppression of single-particle tunneling and a phase diagram with superconducting and non-Fermi-liquid phases.

Contribution

It introduces a gauge theory framework with opposite charge fermions to analyze interlayer tunneling effects in non-Fermi-liquid metals near magnetic transitions.

Findings

Single-particle tunneling is suppressed at low energies.

Pair tunneling leads to a phase diagram with superconducting and non-Fermi-liquid phases.

Results are compatible with copper-oxide superconductor behaviors.

Abstract

We study the effect of interlayer tunneling in the gauge theory describing a quasi-two-dimensional paramagnetic metal close to a second-order or weakly first-order antiferromagnetic phase boundary. In that theory, two species of fermions have opposite (rather than equal) charges with respect to the gauge field. We find that single-particle interlayer tunneling is suppressed at low energies. The effect of pair tunneling is analyzed within the $(3-d)$ expansion. The resulting phase diagram has superconducting and non-Fermi-liquid normal phases, and so is compatible with that of the copper-oxide superconductors.