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Vortices in Bose-Einstein condensates with $mathcal{PT}$-symmetric gain and loss

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 نشر من قبل Holger Cartarius
 تاريخ النشر 2017
  مجال البحث فيزياء
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We investigate vortex excitations in dilute Bose-Einstein condensates in the presence of complex $mathcal{PT}$-symmetric potentials. These complex potentials are used to describe a balanced gain and loss of particles and allow for an easier calculation of stationary states in open systems than in a full dynamical calculation including the whole environment. We examine the conditions under which stationary vortex states can exist and consider transitions from vortex to non-vortex states. In addition, we study the influences of $mathcal{PT}$ symmetry on the dynamics of non-stationary vortex states placed at off-center positions.



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