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Observation of vortex phase singularities in Bose-Einstein condensates

S. Inouye·S. Gupta·T. Rosenband·A. P. Chikkatur·A. Görlitz·T. L. Gustavson·A. E. Leanhardt·D. E. Pritchard·W. Ketterle
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Abstract

We have observed phase singularities due to vortex excitation in Bose-Einstein condensates. Vortices were created by moving a laser beam through a condensate. They were observed as dislocations in the interference fringes formed by the stirred condensate and a second unperturbed condensate. The velocity dependence for vortex excitation and the time scale for re-establishing a uniform phase across the condensate were determined.

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S. Inouye, S. Gupta, T. Rosenband, A. P. Chikkatur, A. Görlitz, T. L. Gustavson, A. E. Leanhardt, D. E. Pritchard, W. Ketterle. 2001-04-23. Observation of vortex phase singularities in Bose-Einstein condensates. https://doi.org/10.1103/physrevlett.87.080402

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