Dynamics of vector dark soliton induced by the Rabi coupling in one-dimensional trapped Bose-Einstein condensates

The Rabi coupling between two components of Bose-Einstein condensates is used to controllably change ordinary dark soliton into dynamic vector dark soliton or ordinary vector dark soliton. When all inter- and intraspecies interactions are equal, the dynamic vector dark soliton is exactly constructed by two sub-dark-solitons, which oscillate with the same velocity and periodically convert with each other. When the interspecies interactions deviate from the intraspecies ones, the whole soliton can maintain its essential shape, but the sub-dark-soliton becomes inexact or is broken. This study indicates that the Rabi coupling can be used to obtain various vector dark solitons.