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Explaining critical angular velocities of the vortex formation in a stirred Bose-Einstein condensate

A. A. Kozhevnikov
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Abstract

The problem of explanation of the critical angular velocity $Ω_c$ when the formation of a vortex in the stirred Bose-Einstein condensate becomes energetically possible, is considered in the framework of the variational approach. The origin of smallness of the calculated $Ω_c$ in comparison with the measured values which takes place for pure quantum state with the unit angular momentum per condensed particle, is uncovered. The agreement with the measured $Ω_c$ is achieved upon admitting a small admixture of the zero angular momentum state in the wave function of the one-vortex quantum state prepared after stirring. The portion of this admixture amounts to 10 - 13 % of the total condensed atoms. Possible test of this hypothesis is proposed.

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A. A. Kozhevnikov. 2000-11-08. Explaining critical angular velocities of the vortex formation in a stirred Bose-Einstein condensate. https://doi.org/10.1134/1.1351200

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