Vortices near the Mott phase of a trapped Bose-Einstein condensate

TL;DR

This paper theoretically investigates how proximity to the Mott insulating phase influences vortex structures in a rotating trapped Bose-Einstein condensate, predicting observable vortex configurations and their experimental signatures.

Contribution

It introduces a model describing vortex behavior near the Mott phase in a trapped BEC, highlighting novel vortex arrangements influenced by the insulating state.

Findings

Vortices can form a ring at a fixed radius from the trap center.

Vortices can coalesce into a giant vortex at the center.

Time-of-flight expansion can reveal these vortex structures.

Abstract

We present a theoretical study of vortices within a harmonically trapped Bose-Einstein condensate in a rotating optical lattice. We find that proximity to the Mott insulating state dramatically effects the vortex structures. To illustrate we give examples in which the vortices: (i) all sit at a fixed distance from the center of the trap, forming a ring, or (ii) coalesce at the center of the trap, forming a giant vortex. We model time-of-flight expansion to demonstrate the experimental observability of our predictions.