Bloch Oscillations of Two-Component Bose--Einstein Condensates in Optical Lattices

We study the Bloch oscillations of two-component Bose--Einstein condensates trapped in spin-dependent optical lattices. The influence of the intercomponent atom interaction on the system is discussed in detail. Accelerated breakdown of the Bloch oscillations and revival phenomena are found respectively for the repulsive and attractive case. For both the cases, the system will finally be set in a quantum self-trapping state due to dynamical instability.