title: Rotating ground states of trapped atoms in a Bose-Einstein condensate with arbitrary two-body interactions.
abstract: In a k-dimensional system of weakly interacting Bose atoms trapped by a spherically symmetric and harmonic external potential, an exact expression is obtained for the rotating ground states at a fixed angular momentum. The result is valid for arbitrary interactions obeying minimal physical requirements. Depending on the sign of a modified scattering length, it reduces to either a collective rotation or a condensed vortex state, with no alternative. The ground state can undergo a kind of quantum phase transition when the shape of the interaction potential is smoothly varied.
authors.affiliation: Grand Accélérateur National d'Ions Lourds, BP 55027, F-14076, Caen Cedex 5, France.
authors.forename: O K
authors.initials: OK
authors.lastname: Vorov
authors.forename: M S
authors.initials: MS
authors.lastname: Hussein
authors.forename: P
authors.initials: P
authors.lastname: Van Isacker