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Time-dependent multi-orbital mean-field for fragmented Bose-Einstein condensates

O. E. Alon·A. I. Streltsov·L. S. Cederbaum
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Abstract

The evolution of Bose-Einstein condensates is usually described by the famous time-dependent Gross-Pitaevskii equation, which assumes all bosons to reside in a single time-dependent orbital. In the present work we address the evolution of fragmented condensates, for which two (or more) orbitals are occupied, and derive a corresponding time-dependent multi-orbital mean-field theory. We call our theory TDMF($n$), where $n$ stands for the number of evolving fragments. Working equations for a general two-body interaction between the bosons are explicitly presented along with an illustrative numerical example.

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O. E. Alon, A. I. Streltsov, L. S. Cederbaum. 2006-07-19. Time-dependent multi-orbital mean-field for fragmented Bose-Einstein condensates. https://doi.org/10.1016/j.physleta.2006.10.048

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