On the effect of the thermal gas component to the stability of vortices in trapped Bose-Einstein condensates
arXiv:cond-mat/0203257 · doi:10.1088/0953-4075/35/19/302
Abstract
We study the stability of vortices in trapped single-component Bose-Einstein condensates within self-consistent mean-field theories--especially we consider the Hartree-Fock-Bogoliubov-Popov theory and its recently proposed gapless extensions. It is shown that for sufficiently repulsively interacting systems the anomalous negative-energy modes related to vortex instabilities are lifted to positive energies due to partial filling of the vortex core with noncondensed gas. Such a behavior implies that within these theories the vortex states are eventually stable against transfer of condensate matter to the anomalous core modes. This self-stabilization of vortices, shown to occur under very general circumstances, is contrasted to the predictions of the non-self-consistent Bogoliubov approximation, which is known to exhibit anomalous modes for all vortex configurations and thus implying instability of these states. In addition, the shortcomings of these approximations in describing the properties of vortices are analysed, and the need of a self-consistent theory taking properly into account the coupled dynamics of the condensate and the noncondensate atoms is emphasized.
8 pages
References in corpus (8)
- Vortices in a trapped dilute Bose-Einstein condensate
- Vortex Nucleation in a Stirred Bose-Einstein Condensate
- Vortex nucleation in Bose-Einstein condensates in an oblate, purely magnetic potential
- Vortex nucleation and hysteresis phenomena in rotating Bose-Einstein condensates
- Structural instability of vortices in Bose-Einstein condensates
- Direct observation of irrotational flow and evidence of superfluidity in a rotating Bose-Einstein condensate
- Structure and Stability of Vortices in Dilute Bose-Einstein Condensates at Ultralow Temperatures
- Adiabaticity Criterion for Moving Vortices in Dilute Bose-Einstein Condensates