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arXiv · 0911.5353

Multiple vortex-antivortex pair generation in magnetic nanodots

Yuri Gaididei·Volodymyr P. Kravchuk·Denis D. Sheka·Franz G. Mertens
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Abstract

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 $m=0,\pm n,\pm 2n$. 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.

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Yuri Gaididei, Volodymyr P. Kravchuk, Denis D. Sheka, Franz G. Mertens. 2010-02-09. Multiple vortex-antivortex pair generation in magnetic nanodots. https://doi.org/10.1103/physrevb.81.094431

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