Nucleation of vortex arrays in rotating anisotropic Bose-Einstein condensates - art. no. 011601

The nucleation of vortices and the resulting structures of vortex arrays in dilute, trapped, zero-temperature Bose-Einstein condensates are investigat ed numerically. Vortices are generated by rotating a three-dimensional, ani sotropic harmonic atom trap. The condensate ground state is obtained by pro pagating the Gross-Pitaevskii equation in imaginary time. Vortices first ap pear at a rotation frequency significantly larger than the critical frequen cy for vortex stabilization, consistent with a critical velocity mechanism for vortex nucleation. At higher frequencies, the structures of the vortex arrays are strongly influenced by trap geometry.