Tunneling dynamics of Bose-Einstein condensates with Feshbach resonances -art. no. 023610

We study tunneling dynamics of atomic pairs in Bose-Einstein condensates wi th Feshbach resonances. It is shown that the tunneling of the atomic pairs depends on not only the tunneling coupling between the atomic condensate an d the molecular condensate, but also the interatomic nonlinear interactions and the initial number of atoms in these condensates. It is found that in addition to oscillating tunneling current between the atomic condensate and the molecular condensate, the nonlinear atomic-pair tunneling dynamics sus tains a self-locked population imbalance: a macroscopic quantum self-trappi ng effect. The influence of decoherence induced by noncondensate atoms on t he tunneling dynamics is investigated. It is shown that decoherence suppres ses atomic-pair tunneling.