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Dynamics of Pinned Magnetic Vortices

R. L. Compton·P. A. Crowell
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Abstract

We observe the dynamics of a single magnetic vortex in the presence of a random array of pinning sites. At low excitation amplitudes, the vortex core gyrates about its equilibrium position with a frequency that is characteristic of a single pinning site. At high amplitudes, the frequency of gyration is determined by the magnetostatic energy of the entire vortex, which is confined in a micron-scale disk. We observe a sharp transition between these two amplitude regimes that is due to depinning of the vortex core from a local defect. The distribution of pinning sites is determined by mapping fluctuations in the frequency as the vortex core is displaced by a static in-plane magnetic field.

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R. L. Compton, P. A. Crowell. 2006-07-04. Dynamics of Pinned Magnetic Vortices. https://doi.org/10.1103/physrevlett.97.137202

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