Landau-Zener tunneling in spin-orbit-coupled Bose-Einstein condensates in bichromatic optical lattices

Landau-Zener transition probability between Bloch bands is carefully investigated in Bose-Einstein condensates belonging to bichromatic optical lattices. The role of the spin-orbit coupling, the energy detuning, the relative phases and depth of primary and secondary lattice are mapped out for the corresponding transition. We find that Landau-Zener tunneling probability strongly depends on the spin-orbit coupling and relative phases of the lattices when the depth of the prime lattice is less than critical values. It is also found that the nonzero transition probabilities mainly occur in the higher Bloch band gaps when the spin-orbit coupling is presented.