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arXiv · 2007.02239

Topological transition from superuid vortex rings to isolated knots and links

Wen-Kai Bai·Tao Yang·Wu-Ming Liu
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Abstract

Knots and links are fundamental topological objects play a key role in both classical and quantum fluids. In this research, we propose a novel scheme to generate torus vortex knots and links through the reconnections of vortex rings perturbed by Kelvin waves in trapped Bose-Einstein condensates. We observe a new phenomenon in a confined superfluid system in which the transfer of helicity between knots/links and coils can occur in both directions with different pathways. The pathways of topology transition can be controlled through designing specific initial states. The generation of a knot or link can be achieved by setting the parity of the Kelvin wave number. The stability of knots/links can be improved greatly with tunable parameters, including the ideal relative angle and the minimal distance between the initial vortex rings.

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Wen-Kai Bai, Tao Yang, Wu-Ming Liu. 2020-07-05. Topological transition from superuid vortex rings to isolated knots and links. https://doi.org/10.1103/physreva.102.063318

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