Phase coherence, visibility, and the superfluid--Mott-insulator transition on one-dimensional optical lattices

TL;DR

This paper uses quantum Monte-Carlo simulations to analyze phase coherence and visibility in one-dimensional optical lattices, revealing signatures of the superfluid--Mott-insulator transition and the melting of Mott domains.

Contribution

It provides detailed simulation results linking visibility features to the evolution of density profiles during the transition, highlighting the role of interaction strength.

Findings

Visibility features match experimental observations

Superfluid and Mott-insulating domains can stall in their evolution

Visibility signals the melting of Mott domains with densities > 1

Abstract

We study the phase coherence and visibility of trapped atomic condensates on one-dimensional optical lattices, by means of quantum Monte-Carlo simulations. We obtain structures in the visibility similar to the kinks recently observed experimentally by Gerbier et.al.[Phy. Rev. Lett. 95, 050404 (2005); Phys. Rev. A 72, 053606 (2005)]. We examine these features in detail and offer a connection to the evolution of the density profiles as the depth of the lattice is increased. Our simulations reveal that as the interaction strength, U, is increased, the evolution of superfluid and Mott-insulating domains stall for finite intervals of U. The density profiles do not change with increasing U. We show here that in one dimension the visibility provides unequivocal signatures of the melting of Mott domains with densities larger than one.