Selective distillation phenomenon in two-species Bose-Einstein condensates in open boundary optical lattices

We investigate the formation of discrete breathers (DBs) and the dynamics of the mixture of two-species Bose-Einstein condensates (BECs) in open boundary optical lattices using the discrete nonlinear Schodinger equations. The results show that the coupling of intra- and interspecies interaction can lead to the existence of pure single-species DBs and symbiotic DBs. Furthermore, we find that there is a selective distillation phenomenon in the dynamics of the mixture of two-species BECs. Therefore, one can selectively distil one species from the mixture of two-species BECs and can even control its purity by adjusting the intra- and interspecies interaction in optical lattices. Our selective distillation mechanism may find potential application in quantum information storage and quantum information processing based on multi-species atoms.