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Critical Velocity of Superfluid Flow past Large Obstacles in Bose-Condensates

J. S. Stiessberger·W. Zwerger
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Abstract

By considering the stability of potential flow of a superfluid around large obstacles of size R, we derive an analytical result for the critical velocity which is of order v_c \sim \hbar / mR, scaling inversely with obstacle size, in contrast to what is obtained from a Landau criterion. Our results are compared with numerical solutions of the Gross-Pitaevskii equation and with recent measurements of the critical velocity in Bose-Einstein condensates of dilute atomic gases.

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J. S. Stiessberger, W. Zwerger. 2000-06-27. Critical Velocity of Superfluid Flow past Large Obstacles in Bose-Condensates. https://doi.org/10.1103/physreva.62.061601

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