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arXiv · 1812.08699

Two-Step Production of Resonant Bose-Einstein Condensates

M. W. C. Sze·J. L. Bohn
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Abstract

Producing a substantial and stable resonant Bose-Einstein condensate (BEC) has proven to be a challenging experimental task due to heating and three-body losses that may occur even before the gas comes to thermal equilibrium. In this paper, by considering only two-body correlations, we note that a sudden quench from small to large scattering lengths may not be the best way to prepare a resonant BEC. As an alternative, we propose a two-step scheme that involves an intermediate scattering length, between $0$ and $\infty$, which serves to maximize the transfer probability of $N$ bosons of mass $m$ in a harmonic trap with frequency $\omega$. We find that the intermediate scattering length should be $a\approx3.16N^{-2/3}\sqrt{\hbar/(m\omega)}$ to produce an optimum transition probability of $1.03N^{-1/6}$.

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M. W. C. Sze, J. L. Bohn. 2018-12-20. Two-Step Production of Resonant Bose-Einstein Condensates. https://doi.org/10.1103/physreva.99.033606

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