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Consequence of superfluidity on the expansion of a rotating Bose-Einstein condensate

Mark Edwards·Charles W. Clark·P. Pedri·L. Pitaevskii·S. Stringari
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Abstract

We study the time evolution of a rotating condensate, that expands after being suddenly released from the confining trap, by solving the hydrodynamic equations of irrotational superfluids. For slow initial rotation speeds, $Ω_{0}$, we find that the condensate's angular velocity increases rapidly to a maximum value and this is accompanied by a minimum in the deformation of the condensate in the rotating plane. During the expansion the sample makes a global rotation of approximately $π/2$, where the exact value depends on $Ω_{0}$. This minimum deformation can serve as an easily detectable signature of superfluidity in a Bose--Einstein condensate.

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Mark Edwards, Charles W. Clark, P. Pedri, L. Pitaevskii, S. Stringari. 2001-06-05. Consequence of superfluidity on the expansion of a rotating Bose-Einstein condensate. https://doi.org/10.1103/physrevlett.88.070405

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