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arXiv · 1705.04364

Macroscopic Quantum Tunneling Escape of Bose-Einstein Condensates

Xinxin Zhao·Diego A. Alcala·Marie A. McLain·Kenji Maeda·Shreyas Potnis·Ramon Ramos·Aephraim M. Steinberg·Lincoln D. Carr
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Abstract

Recent experiments on macroscopic quantum tunneling reveal a non-exponential decay of the number of atoms trapped in a quasibound state behind a potential barrier. Through both experiment and theory, we demonstrate this non-exponential decay results from interactions between atoms. Quantum tunneling of tens of thousands of 87 Rb atoms in a Bose-Einstein condensate is modeled by a modified Jeffreys-Wentzel-Kramers-Brillouin model, taking into account the effective time-dependent barrier induced by the mean-field. Three-dimensional Gross-Pitaevskii simulations corroborate a mean-field result when compared with experiments. However, with one-dimensional modeling using time-evolving block decimation, we present an effective renormalized mean-field theory that suggests many-body dynamics for which a bare mean-field theory may not apply.

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Xinxin Zhao, Diego A. Alcala, Marie A. McLain, Kenji Maeda, Shreyas Potnis, Ramon Ramos, Aephraim M. Steinberg, Lincoln D. Carr. 2017-05-11. Macroscopic Quantum Tunneling Escape of Bose-Einstein Condensates. https://doi.org/10.1103/physreva.96.063601

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