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arXiv · 2204.00246

Fluctuation assisted collapses of Bose-Einstein condensates

Junqiao Pan·Yuqi Wang·Tao Shi·Su Yi
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Abstract

We study the collapse dynamics of a Bose-Einstein condensate subjected to a sudden change of the scattering length to a negative value by adopting the self-consistent Gaussian state theory for mixed states. Compared to the Gross-Pitaevskii and the Hartree-Fock-Bogoliubov approaches, both fluctuations and three-body loss are properly treated in our theory. We find a new type of collapse assisted by fluctuations which amplify the attractive interaction between atoms. Moreover, the calculation of the fluctuated atoms, the entropy, and the second-order correlation function showed that the collapsed gas was significantly deviated from a pure state.

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Junqiao Pan, Yuqi Wang, Tao Shi, Su Yi. 2022-04-01. Fluctuation assisted collapses of Bose-Einstein condensates. https://doi.org/10.1088/1572-9494%2Fac60fb

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