Quantum melting of a crystal of dipolar bosons

TL;DR

This paper studies the quantum melting transition of a two-dimensional crystal of dipolar bosons, combining analytical and quantum Monte Carlo methods to explore phase behavior relevant to ultracold molecule experiments.

Contribution

It provides an analytical description of the crystalline phase and evidence for a first order melting transition using quantum Monte Carlo simulations.

Findings

Evidence for a first order quantum melting transition.

Identification of experimentally accessible parameters for observing melting.

Analysis of the potential for supersolid phase near melting point.

Abstract

We investigate the behaviour of dipolar bosons in two dimensions. We describe the large density crystalline limit analytically while we use quantum Monte-Carlo to study the melting toward the Bose-Einstein condensate. We find strong evidence for a first order transition. We characterize the window of experimentally accessible parameters in the context of ultracold bosons and show that observing the quantum melting should be within grasp once one is able to form cold heteronuclear molecules. Close to the melting, we can not conclude on the existence of a supersolid phase due to an insufficient overlap of our variational Bijl-Jastrow Ansatz with the actual ground state.