Quantum simulations of the superfluid-insulator transition for two-dimensional, disordered, hard-core bosons

TL;DR

This paper introduces two new quantum Monte Carlo methods to study the superfluid-insulator transition in disordered two-dimensional hard-core bosons, confirming the dynamical exponent z=2 predicted by theory.

Contribution

The paper presents two novel quantum Monte Carlo algorithms tailored for zero and finite temperatures to investigate phase transitions in disordered bosonic systems.

Findings

Dynamical exponent z=2 confirmed for the transition

Methods applicable to zero and finite temperature regimes

Supports theoretical predictions by Fisher et al.

Abstract

We introduce two novel quantum Monte Carlo methods and employ them to study the superfluid-insulator transition in a two-dimensional system of hard-core bosons. One of the methods is appropriate for zero temperature and is based upon Green's function Monte Carlo; the other is a finite-temperature world-line cluster algorithm. In each case we find that the dynamical exponent is consistent with the theoretical prediction of $z=2$ by Fisher and co-workers.