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arXiv · 1408.0158

Realizing PT-symmetric non-Hermiticity with ultra-cold atoms and Hermitian multi-well potentials

Manuel Kreibich·Jörg Main·Holger Cartarius·Günter Wunner
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Abstract

We discuss the possibility of realizing a non-Hermitian, i.e. an open two-well system of ultra-cold atoms by enclosing it with additional time-dependent wells that serve as particle reservoirs. With the appropriate design of the additional wells PT-symmetric currents can be induced to and from the inner wells, which support stable solutions. We show that interaction in the mean-field limit does not destroy this property. As a first method we use a simplified variational ansatz leading to a discrete nonlinear Schrödinger equation. A more accurate and more general variational ansatz is then used to confirm the results.

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Manuel Kreibich, Jörg Main, Holger Cartarius, Günter Wunner. 2014-08-01. Realizing PT-symmetric non-Hermiticity with ultra-cold atoms and Hermitian multi-well potentials. https://doi.org/10.1103/physreva.90.033630

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