Phase diagram of quantized vortices in a trapped Bose-Einstein condensed gas

We investigate the thermodynamic stability of quantized vortices in a dilut e Bose gas confined by a rotating harmonic trap at finite temperature. Inte ratomic forces play a crucial role in characterizing the resulting phase di agram, especially in the large N Thomas-Fermi regime. We show that the crit ical temperature for the creation of stable vortices exhibits a maximum as a function of the frequency of the rotating trap, and that the correspondin g transition is associated with a discontinuity in the number of atoms in t he condensate. Possible strategies for approaching the vortical region are discussed. [S0031-9007(99)09252-2].