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

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 affects 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 the imaging of these structures by calculating time-of-flight column densities. As in the absence of the optical lattice, the vortices are much more easily observed in a time-of-flight image than \emph{in-situ}. \\ \\ D.~S. Goldbaum and E.~J. Mueller, \emph{Vortices near the Mott phase of a trapped Bose-Einstein condensate}, arXiv:0808.1548.