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arXiv · 1110.5757

Vortex knots in a Bose-Einstein condensate

Davide Proment·Miguel Onorato·Carlo F. Barenghi
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Abstract

We present a method for numerically building a vortex knot state in the superfluid wave-function of a Bose-Einstein condensate. We integrate in time the governing Gross-Pitaevskii equation to determine evolution and stability of the two (topologically) simplest vortex knots which can be wrapped over a torus. We find that the velocity of a vortex knot depends on the ratio of poloidal and toroidal radius: for smaller ratio, the knot travels faster. Finally, we show how unstable vortex knots break up into vortex rings.

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Davide Proment, Miguel Onorato, Carlo F. Barenghi. 2011-10-26. Vortex knots in a Bose-Einstein condensate. https://doi.org/10.1103/physreve.85.036306

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