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arXiv · 1906.08664

Vortex Lattice Formation in Dipolar Bose-Einstein Condensates via Rotation of the Polarization

Abstract

The behaviour of a harmonically trapped dipolar Bose-Einstein condensate with its dipole moments rotating at angular frequencies lower than the transverse harmonic trapping frequency is explored in the co-rotating frame. We obtain semi-analytical solutions for the stationary states in the Thomas-Fermi limit of the corresponding dipolar Gross-Pitaevskii equation and utilise linear stability analysis to elucidate a phase diagram for the dynamical stability of these stationary solutions with respect to collective modes. These results are verified via direct numerical simulations of the dipolar Gross-Pitaevskii equation, which demonstrate that dynamical instabilities of the co-rotating stationary solutions lead to the seeding of vortices that eventually relax into a triangular lattice configuration. Our results illustrate that rotation of the dipole polarization represents a new route to vortex formation in dipolar Bose-Einstein condensates.

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Srivatsa B. Prasad, Thomas Bland, Brendan C. Mulkerin, Nick G. Parker, Andrew M. Martin. 2019-08-08. Vortex Lattice Formation in Dipolar Bose-Einstein Condensates via Rotation of the Polarization. https://doi.org/10.1103/physreva.100.023625

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