title: Landau levels and the Thomas-fermi structure of rapidly rotating bose-einstein condensates.
abstract: We show that, within mean-field theory, the density profile of a rapidly rotating harmonically trapped Bose-Einstein condensate is of the Thomas-Fermi form as long as the number of vortices is much larger than unity. Two forms of the condensate wave function are explored: (i) the lowest Landau level (LLL) wave function with a regular lattice of vortices multiplied by a slowly varying envelope function, which gives rise to components in higher Landau levels; (ii) the LLL wave function with a nonuniform vortex lattice. From variational calculations, we find it most favorable energetically to retain the LLL form of the wave function but to allow the vortices to deviate slightly from a regular lattice. The predicted distortions of the lattice are small, but in accord with recent measurements at lower rates of rotation.
authors.affiliation: Department of Physics, University of Tokyo, Tokyo 113-0033, Japan.
authors.forename: Gentaro
authors.initials: G
authors.lastname: Watanabe
authors.forename: Gordon
authors.initials: G
authors.lastname: Baym
authors.forename: C J
authors.initials: CJ
authors.lastname: Pethick