Change in the adiabatic invariant in a nonlinear two-mode model of Feshbach resonance passage
arXiv:nlin/0611007 · doi:10.1016/j.physd.2007.06.001
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.
17 pages, 4 figures