Strongly Interacting Atom Lasers in Three Dimensional Optical Lattices

TL;DR

This paper demonstrates how the dynamical melting of a Mott insulator in 3D optical lattices can produce strongly interacting atom lasers with predictable condensation momenta, using mean-field and exact methods.

Contribution

It analytically determines the condensation momenta in a strongly interacting 3D lattice and shows the linear scaling of condensate occupation with initial atom number.

Findings

Condensation occurs at nonzero momenta after melting.

Condensation momenta depend simply on hopping amplitudes.

Condensate occupation scales linearly with initial atom number.

Abstract

We show that the dynamical melting of a Mott insulator in a three-dimensional lattice leads to condensation at nonzero momenta, a phenomenon that can be used to generate strongly interacting atom lasers in optical lattices. For infinite onsite repulsion, the case considered here, the momenta at which bosons condense is determined analytically and found to have a simple dependence on the hopping amplitudes. The occupation of the condensates is shown to scale linearly with the total number of atoms in the initial Mott insulator. Our results are obtained using a Gutzwiller-type mean-field approach, gauged against exact diagonalization solutions of small systems.