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Quantum knots in Bose-Einstein condensates created by counterdiabatic control

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 نشر من قبل Tuomas Ollikainen
 تاريخ النشر 2017
  مجال البحث فيزياء
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We theoretically study the creation of knot structures in the polar phase of spin-1 BECs using the counterdiabatic protocol in an unusual fashion. We provide an analytic solution to the evolution of the external magnetic field that is used to imprint the knots. As confirmed by our simulations using the full three-dimensional spin-1 Gross-Pitaevskii equation, our method allows for the precise control of the Hopf charge as well as the creation time of the knots. The knots with Hopf charge exceeding unity display multiple nested Hopf links.

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