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arXiv · 1901.11083

Condensates in annuli: Dimensionality of the variance

Ofir E. Alon
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Abstract

Static and dynamic properties of Bose-Einstein condensates in annular traps are investigated by solving the many-boson Schr\"odinger equation numerically accurately using the multiconfigurational time-dependent Hartree for bosons method. We concentrate on weakly-interacting bosons exhibiting low depletion. Analysis of the mean-field position variance, which accounts for the shape of the density only, and the many-body position variance, which incorporates a tiny amount of excitations through the reduced two-particle density matrix, shows that the former behaves essentially as a quasi-one-dimensional quantity whereas the latter as a two-dimensional quantity. This brings another dimension to the physics of bosons in ring-shaped traps.

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Ofir E. Alon. 2019-01-30. Condensates in annuli: Dimensionality of the variance. https://doi.org/10.1080/00268976.2019.1587533

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