Quantum Critical Behavior of Disordered Superfluids

TL;DR

This paper investigates the quantum critical behavior of disordered superfluids using a double epsilon expansion, revealing an infrared stable fixed point that indicates localization in the superfluid state.

Contribution

It introduces a novel double epsilon expansion approach to analyze the quantum criticality of disordered Bose systems, identifying a stable fixed point.

Findings

Identification of an infrared stable fixed point in the disordered superfluid model.

Demonstration of localization phenomena in the superfluid state.

Application of double epsilon expansion to non-relativistic Bose theories with disorder.

Abstract

The quantum critical behavior of an interacting, non-relativistic Bose theory with quenched disorder randomly distributed in space is investigated. The renormalization group is carried out in a double $\epsilon$ expansion, where one $\epsilon$ is the deviation of the effective space-time dimensionality from 4, while the other denotes the number of time dimensions. The disordered theory, which displays localization in the superfluid state, is shown to possess an infrared stable fixed point.