Dirty-boson physics with magnetic insulators

TL;DR

This paper reviews recent theoretical and experimental research on dirty bosons in quantum magnetism, focusing on phase transitions and critical behavior in disordered magnetic insulators under strong magnetic fields.

Contribution

It highlights how disordered magnetic insulators serve as controlled systems to study the Bose-glass to superfluid transition, combining simulations and experiments to understand critical phenomena.

Findings

Insights into the phase transition from Bose-glass to superfluid.

Identification of disordered magnetic insulators as model systems.

Analysis of critical temperature scaling near quantum critical points.

Abstract

We review recent theoretical and experimental efforts aimed at the investigation of the physics of interacting disordered bosons (so-called dirty bosons) in the context of quantum magnetism. The physics of dirty bosons is relevant to a wide variety of condensed matter systems, encompassing Helium in porous media, granular superconductors and ultracold atoms in disordered optical potentials, to cite a few. Nevertheless, the understanding of the transition from a localized, Bose-glass phase to an ordered, superfluid condensate phase still represents a fundamentally open problem. Still to be constructed is also a quantitative description of the highly inhomogeneous and strongly correlated phases connected by the transition. We discuss how disordered magnetic insulators in a strong magnetic field can provide a well controlled realization of the above transition. Combining numerical simulations with experiments on real materials can shed light on some fundamental properties of the critical behavior, such as the scaling of the critical temperature to condensation close to the quantum critical point.