Superfluid--Insulator Transition in Strongly Disordered One-dimensional Systems

TL;DR

This paper develops an exact renormalization-group theory for the superfluid-insulator transition in disordered 1D systems, clarifying the interplay of different criticalities and supporting findings with quantum Monte Carlo simulations.

Contribution

It introduces a novel asymptotically exact RG approach that captures the complex critical behavior in disordered 1D Bose systems, enhancing understanding of their phase diagram.

Findings

New RG theory describing criticality in disordered 1D systems

Quantum Monte Carlo simulations supporting the theoretical predictions

Refined phase diagram of the disordered Bose-Hubbard model at unit filling

Abstract

We present an asymptotically exact renormalization-group theory of the superfluid--insulator transition in one-dimensional disordered systems, with emphasis on an accurate description of the interplay between the Giamarchi--Schulz (instanton--anti-instanton) and weak-link (scratched-XY) criticalities. Combining the theory with extensive quantum Monte Carlo simulations allows us to shed new light on the ground-state phase diagram of the one-dimensional disordered Bose-Hubbard model at unit filling.