The interaction of a magnetic vortex with a rotating magnetic field causes the nucleation of a vortex--antivortex pair leading to a vortex polarity switching. The key point of this process is the creation of a dip, which can be interpreted as a nonlinear resonance in the system of certain magnon modes with nonlinear coupling. The usually observed single-dip structure is a particular case of a multidip structure. The dynamics of the structure with n dips is described as the dynamics of nonlinearly coupled modes with azimuthal numbers m=0,±n,±2n. The multidip structure with arbitrary number of vortex antivortex pairs can be obtained in vortex-state nanodisk using a space- and time-varying magnetic field. A scheme of a possible experimental setup for multidip structure generation is proposed.
@article{arxiv.0911.5353,
title = {Multiple vortex-antivortex pair generation in magnetic nanodots},
author = {Yuri Gaididei and Volodymyr P. Kravchuk and Denis D. Sheka and Franz G. Mertens},
journal= {arXiv preprint arXiv:0911.5353},
year = {2011}
}