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arXiv · 2104.11916

Many-body state and dynamic behaviour of the pair-correlation function of a small Bose-Einstein condensate confined in a ring potential

Abstract

We investigate the many-body state and the static and the dynamic behaviour of the pair-correlation function of a Bose-Einstein condensate with a finite atom number, which is confined in a quasi-one-dimensional toroidal/annular potential, both for repulsive, and for attractive interactions. We link the dynamic pair-correlation function that we evaluate with the problem of quantum time crystals. For weak repulsive interatomic interactions and a finite number of atoms the pair-correlation function shows a periodic temporal behaviour, which disappears in the limit of a large atom number, in agreement with general arguments. Finally we provide some insight into older results of attractive interactions, where the time-crystalline behaviour exists only in the limit of a large atom number.

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A. Roussou, J. Smyrnakis, M. Magiropoulos, G. M. Kavoulakis. 2021-04-24. Many-body state and dynamic behaviour of the pair-correlation function of a small Bose-Einstein condensate confined in a ring potential. https://doi.org/10.1007/s10909-022-02831-8

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