Dissipation and vortex creation in Bose-Einstein condensed gases - art. no. 051603

We solve the Gross-Pitaevskii equation to study energy transfer from an osc illating "object" to a trapped Bose-Einstein condensate. Two regimes are fo und: for object velocities below a critical value, energy is transferred by excitation of phonons at the motion extrema; while above the critical velo city, energy transfer is via vortex formation. The second regime correspond s to significantly enhanced heating, in agreement with a recent experiment.