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arXiv · 1509.05656

Purity oscillations in Bose-Einstein condensates with balanced gain and loss

Dennis Dast·Daniel Haag·Holger Cartarius·Günter Wunner
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Abstract

In this work we present a new generic feature of PT-symmetric Bose-Einstein condensates by studying the many-particle description of a two-mode condensate with balanced gain and loss. This is achieved using a master equation in Lindblad form whose mean-field limit is a PT-symmetric Gross-Pitaevskii equation. It is shown that the purity of the condensate periodically drops to small values but then is nearly completely restored. This has a direct impact on the average contrast in interference experiments which cannot be covered by the mean-field approximation, in which a completely pure condensate is assumed.

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Dennis Dast, Daniel Haag, Holger Cartarius, Günter Wunner. 2015-09-18. Purity oscillations in Bose-Einstein condensates with balanced gain and loss. https://doi.org/10.1103/physreva.93.033617

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