Competition between Vortex Unbinding and Tunneling in an Optical Lattice

TL;DR

This paper investigates the competition between vortex unbinding and tunneling in 2D Bose gases within an optical lattice, identifying a deconfinement transition characterized by coherence and superfluidity signatures.

Contribution

It introduces a detailed analysis of the deconfinement transition driven by tunneling in 2D Bose gases in optical lattices, linking interference patterns and rotational response to superfluidity.

Findings

Identification of a deconfinement transition with increased tunneling

Signature of transition in interference patterns

Measurement of superfluidity via rotational response

Abstract

We study a system of two-dimensional Bose gases trapped in minima of a deep one-dimensional optical lattice potential. Increasing the tunneling amplitude between adjacent gases drives a deconfinement transition to a phase where coherence is established between neighboring two-dimensional gases. We compute the signature of this transition in the interference pattern of the system as well as in its rotational response, which provides a direct measurement of the superfluidity in the system.