Spinor Bose-Einstein condensates with many vortices

Vortex-lattice structures of antiferromagnetic spinor Bose-Einstein condensates with hyperfine spin F=1 are investigated theoretically based on the Ginzburg-Pitaevskii equations near T{sub c}. The Abrikosov lattice with clear core regions is never found to be stable at any rotation drive {omega}. Instead, each component {psi}{sub i} (i=0,{+-}1) prefers to shift the core locations away from the others to realize almost uniform order-parameter amplitude with complicated magnetic-moment configurations. This system is characterized by many competing metastable structures so that quite a variety of vortices may be realized with a small change in external parameters.