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Change in the adiabatic invariant in a nonlinear two-mode model of Feshbach resonance passage

A. P. Itin·A. A. Vasiliev·S. Watanabe·G. Krishna
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Abstract

Mean-field approach has recently been used to model coupled atom-molecular Bose-Einstein condensates (BEC) and coupled Fermi-Bose condensates near Feshbach resonance. Sweeping of magnetic field across the resonance gives a new (nonlinear) version of Landau-Zener problem. We investigate the structure of the corresponding classical phase space and calculate change in the action which corresponds to finite-rate efficiency of the sweep. We consider the case of non-zero initial action, which corresponds to some finite initial molecular fraction.

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A. P. Itin, A. A. Vasiliev, S. Watanabe, G. Krishna. 2007-05-28. Change in the adiabatic invariant in a nonlinear two-mode model of Feshbach resonance passage. https://doi.org/10.1016/j.physd.2007.06.001

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