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arXiv · 0809.1818

The giant vortex state for a Bose-Einstein condensate in a rotating anharmonic trap : extreme rotation regimes

Nicolas Rougerie
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Abstract

We study the fast rotation limit for a Bose-Einstein condensate in a quadratic plus quartic confining potential within the framework of the two dimensional Gross-Pitaevskii energy functional. As the rotation speed tends to infinity with a proper scaling of the other parameters in the model, a linear limit problem appears for which we are able to derive precise energy estimates. We prove that the energy and density asymptotics of the problem can be obtained by minimizing a simplified one dimensional energy functional. In the case of a fixed coupling constant we also prove that a giant vortex state appears. It is an annulus with pure irrotational flow encircling a central low-density hole around which there is a macroscopic phase circulation.

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Nicolas Rougerie. 2009-12-01. The giant vortex state for a Bose-Einstein condensate in a rotating anharmonic trap : extreme rotation regimes. https://arxiv.org/abs/0809.1818

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