Annihilation of quantized vorticity in a trapped Bose-Einstein condensate via the scattering of density perturbations

P. CAPUZZI; F. FEDERICI; M. P. TOSI

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

Año: 2008 vol. 78 p. 23604 - 236046

1050-2947

   We evaluate the extraction of angular momentum from quantized vortices in trapped Bose-Einstein conden-sates. Within a variational approach we show that the energy barrier between the ground state and the statecontaining an axisymmetric vortex can be crossed in a scattering process by density perturbations. The transferof angular momentum can be made total for suitably chosen density perturbations carrying about 10% of theground-state energy, irrespectively of the number of particles in the condensate. A similar pattern is reproducedby the full solution of the Gross-Pitaevskii equation, although interference and diffusion effects are now seento limit the efficiency of the process.