We consider the motion of individual two-dimensional vortices in general radially symmetric potentials in Bose-Einstein condensates. We find that although in the special case of the parabolic trap there is a logarithmic correction in the dependence of the precession frequency ω on the chemical potential μ, this is no longer true for a general potential V(r)rp. Our calculations suggest that for p>2, the precession frequency scales with μ as ω∼μ-2/p. This theoretical prediction is corroborated by numerical computations, not only at the level of spectral (Bogolyubov-de Gennes) stability analysis by identifying the relevant precession mode dependence on μ but also through direct numerical computations of the vortex evolution in the large-μ, so-called Thomas-Fermi, limit. Additionally, the dependence of the precession frequency on the distance to the trap center of an initially displaced vortex is examined, and the corresponding predictions are tested against numerical results.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics