Landau-Zener tunneling behaviors of Bose-Einstein condensates in a dichromatic optical lattice

With considering Bose-Einstein condensates to be confined in a periodic dichromatic optical lattice, Bloch energy band structure and Landau-Zener tunneling behaviors of the first and second band gaps are studied in this paper. It is shown that when the relative phase between the two lattices increases from 0 to π, the width of the first band gap in the Bloch energy band increases, while the width of the second band gap decreases. Meanwhile, it is found that the depth and the relative phase between the two lattices have both an important effect on Landau-Zener tunneling properties.