Effect of interspecies interactions on the collision properties of bright-bright solitons in two-species Bose-Einstein condensates

Considering the time-dependent interspecies interactions, we study the collision properties of bright-bright solitons in two species Bose-Einstein condensates with the harmonic external potentials. It is shown that the collision behaviors of bright-bright solitons can be controlled by adjusting the strength of interspecies interaction and transverse trapping frequency of harmonic potential. Interestingly, the two separate solitons can merge into a single bound complex due to the stronger attractive interspecies interactions. Especially, a transmission collision is obtained from not only attractive but also repulsive interspecies interaction, different from previous theory. When the interspecies interaction is exponentially decreased, a reflection-transmission collision transition is observed for the repulsive interspecies interaction. Meanwhile, an experimental protocol is designed to observe the collision behaviors of the bright-bright solitons in the currently experimental conditions.