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arXiv · 0709.0405

Metastability of persistent currents in trapped gases of atoms

K. Karkkainen·J. Christensson·G. Reinisch·G. M. Kavoulakis·S. M. Reimann
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Abstract

We examine the conditions that give rise to metastable, persistent currents in a trapped Bose-Einstein condensate. A necessary condition for the stability of persistent currents is that the trapping potential is not a monotonically increasing function of the distance from the trap center. Persistent currents also require that the interatomic interactions are sufficiently strong and repulsive. Finally, any off-center vortex state is shown to be unstable, while a driven gas shows hysteresis.

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K. Karkkainen, J. Christensson, G. Reinisch, G. M. Kavoulakis, S. M. Reimann. 2007-09-04. Metastability of persistent currents in trapped gases of atoms. https://doi.org/10.1103/physreva.76.043627

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