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arXiv · 1903.02042

Quasi-stable quantum vortex knots and links in anisotropic harmonically trapped Bose-Einstein condensates

Christopher Ticknor·Victor P. Ruban·P. G. Kevrekidis
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Abstract

Long-time existence of topologically nontrivial configurations of quantum vortices in the form of torus knots and links in trapped Bose-Einstein condensates is demonstrated numerically within the three-dimensional Gross-Pitaevskii equation with external anisotropic parabolic potential. We find out parametric domains near the trap anisotropy -- axial over planar frequency trapping ratio $λ\approx 1.5-1.6$ where the lifetime of such quasi-stationary rotating vortex structures is many hundreds of typical rotation times. This suggests the potential experimental observability of the structures. We quantify the relevant lifetimes as a function of the model parameters (e.g. $λ$) and initial condition parameters of the knot profile.

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Christopher Ticknor, Victor P. Ruban, P. G. Kevrekidis. 2019-03-05. Quasi-stable quantum vortex knots and links in anisotropic harmonically trapped Bose-Einstein condensates. https://doi.org/10.1103/physreva.99.063604

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