Mott-insulator phase of coupled 1D atomic gases in a 2D optical lattice

TL;DR

This paper investigates the 2D Mott insulator phase of coupled 1D Bose gases in an optical lattice, highlighting how the momentum distribution's behavior depends on interaction regimes, especially distinguishing between MI and Tonks-Girardeau regimes.

Contribution

It reveals that the disappearance of interference patterns is due to strong interactions in 1D tubes, not necessarily the MI phase, clarifying experimental signatures.

Findings

Momentum distribution is highly sensitive to interaction regimes.

Disappearance of interference pattern does not uniquely indicate MI phase.

Strong interactions in 1D tubes can mimic MI signatures.

Abstract

We discuss the 2D Mott insulator (MI) state of a 2D array of coupled finite size 1D Bose gases. It is shown that the momentum distribution in the lattice plane is very sensitive to the interaction regime in the 1D tubes. In particular, we find that the disappearance of the interference pattern in time of flight experiments will not be a signature of the MI phase, but a clear consequence of the strongly interacting Tonks-Girardeau regime along the tubes.