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arXiv · 0809.2007

Nonlinear Dynamics of Bose-Einstein Condensates with Long-Range Interactions

G. Wunner·H. Cartarius·T. Fabčič·P. Köberle·J. Main·T. Schwidder
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Abstract

The motto of this paper is: Let's face Bose-Einstein condensation through nonlinear dynamics. We do this by choosing variational forms of the condensate wave functions (of given symmetry classes), which convert the Bose-Einstein condensates via the time-dependent Gross-Pitaevskii equation into Hamiltonian systems that can be studied using the methods of nonlinear dynamics. We consider in particular cold quantum gases where long-range interactions between the neutral atoms are present, in addition to the conventional short-range contact interaction, viz. gravity-like interactions, and dipole-dipole interactions. The results obtained serve as a useful guide in the search for nonlinear dynamics effects in numerically exact quantum calculations for Bose-Einstein condensates. A main result is the prediction of the existence of stable islands as well as chaotic regions for excited states of dipolar condensates, which could be checked experimentally.

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BibTeXRIS

G. Wunner, H. Cartarius, T. Fabčič, P. Köberle, J. Main, T. Schwidder. 2008-09-11. Nonlinear Dynamics of Bose-Einstein Condensates with Long-Range Interactions. https://doi.org/10.1063/1.3046264

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