The existence of stable or metastable vortex and antivortex states in submicron fer-romagnetic films is reviewed. Using standard simulation methods, the dynamics of anantivortex in a permalloy asteroid geometry is explored. As in the case of the vortexin similarly sized permalloy disks and squares, there is a sub-GHz frequency gyrotropicmode of the core of the antivortices, and a rich spin wave spectrum in the multi-GHzrange. The spin waves are generated in the simulations by using magnetic pulses sim-ilar to those available experimentally, which have been applied to circular and squareparticles of similar sizes in previous research.
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