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arXiv · 1909.08116

Symmetry breaking in interacting ring-shaped superflows of Bose-Einstein condensates

Artem Oliinyk·Igor Yatsuta·Boris Malomed·Alexander Yakimenko
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Abstract

We demonstrate that the evolution of superflows in interacting persistent currents of ultracold gases is strongly affected by symmetry breaking of the quantum vortex dynamics. We study counter-propagating superflows in a system of two parallel rings in regimes of weak (a Josephson junction with tunneling through the barrier) and strong (rings merging across a reduced barrier) interactions. For the weakly interacting toroidal Bose-Einstein condensates, formation of rotational fluxons (Josephson vortices) is associated with spontaneous breaking of the rotational symmetry of the tunneling superflows. The influence of a controllable symmetry breaking on the final state of the merging counter-propagating superflows is investigated in the framework of a weakly dissipative mean-field model. It is demonstrated that the population imbalance between the merging flows and the breaking of the underlying rotational symmetry can drive the double-ring system to final states with different angular momenta.

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Artem Oliinyk, Igor Yatsuta, Boris Malomed, Alexander Yakimenko. 2019-10-20. Symmetry breaking in interacting ring-shaped superflows of Bose-Einstein condensates. https://doi.org/10.3390/sym11101312

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