Stationary rings of vortices in nonrotating Bose-Einstein condensates

D. M. JEZEK; P. CAPUZZI; M. GUILLEUMAS; R. MAYOL

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

Año: 2008 vol. 78 p. 53616 - 536167

1050-2947

   We numerically obtain stationary rings of vortices in pancake-shaped Bose-Einstein condensates confined ina three-dimensional nonrotating trap. For this purpose we use a static axisymmetric trapping potential that cansustain locally stable off-axis vortices. We analyze the maximum number of vortices the system can host as afunction of the number of particles. We also show that this system provides a very suitable scenario forpredicting vortex dynamics in inhomogeneous media. Specifically, on the one hand, we derive an exact andsimple analytical expression for the velocity field in a particular vortex position due to the presence of the othervortices of the array. On the other hand, using the fact that in stationary conditions this field should balance allother contributions to the velocity, we investigate the applicability of approximated expressions for the pre-cession velocity obtained in previous works for condensates with a single vortex.