Landau-Zener Tunnelling of Two-Component Bose-Einstein Condensates in Optical Lattices

摘要

We investigate the Landau-Zener tunnelling of two-component Rose-Einstein condensates (BECs) in opticallattices.In the neighborhood of the Rrillouin zone edge,the system can be reduced to two coupled nonlinear two-levelmodels.From the models,we calculate the change of the tunnelling probability for each component with the linearsweeping rate.It is found that the probability for each component exhibits regular oscillating behavior for the largersweeping rate,but for smaller rate the oscillation is irregular.Moreover,the asymmetry of the tunnelling between thetwo components can be induced by the unbalanced initial populations or the inequality of the two self-interactions whenthe cross-interaction between the components exists.The result can not be found in the single component BECs.