Journal of Physics Conference Series
Dynamical stability of coreless vortex states inF= 1 spinor bose-einstein condensates
M Takahashia, Ville Pietilä, Mikko Möttönen, Takeshi Mizushima, K. Machida
Abstract
We investigate the dynamical stability of the coreless vortex state in F = 1 spinor Bose-Einstein condensates, by numerically solving the Gross-Pitaevskii and Bogoliubov-de Gennes equations. We cover both ferromagnetic and antiferromagnetic interaction regions and the magnetizations per particle M from -1 to +1. It is found that the coreless vortex state is dynamically stable in large parameter regions of magnetization M . At M = -1, the hyperfine spin component with vortex winding 2 is dominant, and hence the coreless vortex can spontaneously decay even without dissipation. However, it is found that in the ferromagnetic case, the spin-spin interactions tend to stabilize the state. In the antiferromagnetic case, we find new dynamical instability modes which are not obtained in the ferromagnetic interaction region. In the antiferromagnetic interaction region, the spin-spin interactions can stimulate dynamical instabilities, while there still remains a large stability area in the parameter M . This is because of certain restrictions in inducing dynamical instability.