Characterization of the Bose-glass phase in low-dimensional lattices

TL;DR

This paper uses numerical simulations to analyze the Bose-glass phase in disordered low-dimensional lattices, emphasizing the importance of probability distributions over averages for accurate phase characterization.

Contribution

It introduces a statistical approach to characterize the Bose-glass phase, highlighting the necessity of analyzing distributions of physical quantities in disordered quantum systems.

Findings

Probability distributions are essential for phase diagram characterization.

The Bose-glass phase is stable in disordered low-dimensional lattices.

Finite-size effects influence the interpretation of experimental data.

Abstract

We study by numerical simulation a disordered Bose-Hubbard model in low-dimensional lattices. We show that a proper characterization of the phase diagram on finite disordered clusters requires the knowledge of probability distributions of physical quantities rather than their averages. This holds in particular for determining the stability region of the Bose-glass phase, the compressible but not superfluid phase that exists whenever disorder is present. This result suggests that a similar statistical analysis should be performed also to interpret experiments on cold gases trapped in disordered lattices, limited as they are to finite sizes.