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arXiv · 1303.0132

Spectral singularities in PT-symmetric Bose-Einstein condensates

W. D. Heiss·H. Cartarius·G. Wunner·J. Main
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Abstract

We consider the model of a PT-symmetric Bose-Einstein condensate in a delta-functions double-well potential. We demonstrate that analytic continuation of the primarily non-analytic term |psi|^2 psi - occurring in the underlying Gross-Pitaevskii equation - yields new branch points where three levels coalesce. We show numerically that the new branch points exhibit the behaviour of exceptional points of second and third order. A matrix model which confirms the numerical findings in analytic terms is given.

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W. D. Heiss, H. Cartarius, G. Wunner, J. Main. 2013-03-01. Spectral singularities in PT-symmetric Bose-Einstein condensates. https://doi.org/10.1088/1751-8113/46/27/275307

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