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arXiv · 1702.03846

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

Lukas Schwarz·Holger Cartarius·Ziad H. Musslimani·Jörg Main·Günter Wunner
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Abstract

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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Lukas Schwarz, Holger Cartarius, Ziad H. Musslimani, Jörg Main, Günter Wunner. 2017-04-21. Vortices in Bose-Einstein condensates with $\mathcal{PT}$-symmetric gain and loss. https://doi.org/10.1103/physreva.95.053613

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