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Vortex precession in Bose-Einstein condensates: observations with filled and empty cores

B. P. Anderson·P. C. Haljan·C. E. Wieman·E. A. Cornell
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Abstract

We have observed and characterized the dynamics of singly quantized vortices in dilute-gas Bose-Einstein condensates. Our condensates are produced in a superposition of two internal states of 87Rb, with one state supporting a vortex and the other filling the vortex core. Subsequently, the state filling the core can be partially or completely removed, reducing the radius of the core by as much as a factor of 13, all the way down to its bare value. The corresponding superfluid rotation rates, evaluated at the core radius, vary by a factor of 150, but the precession frequency of the vortex core about the condensate axis changes by only a factor of two.

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B. P. Anderson, P. C. Haljan, C. E. Wieman, E. A. Cornell. 2000-05-23. Vortex precession in Bose-Einstein condensates: observations with filled and empty cores. https://doi.org/10.1103/physrevlett.85.2857

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