We investigate the phase structure of two-component Bose-Einstein condensates(BECs) with repulsive intra- and interspecies interactions in the presence ofrespective vortex-antivortex superposition states (VAVSS). We show thatdifferent winding numbers of vortex and antivortex and different intra- andinterspecies interaction strengths may lead to different phase configurations,such as fully separated phases, inlaid separated phases, asymmetric separatedphase, and partially mixed phases, where the density profile of each componentdisplays a petal-like (or modulated petal-like) structure. A phase diagram isgiven for the case of equal unit winding numbers of the vortex and antivortexin respective components, and it is shown that conventional criterion for phaseseparation of two-component BECs is not applicable for the present system dueto the VAVSS. In addition, our nonlinear stability analysis indicates that thetypical phase structures of two-component BECs with VAVSS allow to be detectedin experiments. Moreover, for the case of unequal winding numbers of the vortexand antivortex in respective components, we find that each component in any ofthe possible phase structures is in a cluster state of vortices andantivortices, where the topological defects appear in the form of singlyquantized visible vortex, or hidden vortex, or ghost vortex, depending on thespecific parameters of the system. Finally, a general rule between thevortex-antivortex cluster state and the winding numbers of vortex andantivortex is revealed.
展开▼
