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arXiv · 0901.0864

Non-linear vortex dynamics and transient effects in ferromagnetic disks

X. M. Cheng·K. Buchanan·R. Divan·K. Y. Guslienko·D. J. Keavney
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Abstract

We report a time resolved imaging and micromagnetic simulation study of the relaxation dynamics of a magnetic vortex in the non-linear regime. We use time-resolved photoemission electron microscopy and micromagnetic calculations to examine the emergence of non-linear vortex dynamics in patterned Ni80Fe20 disks in the limit of long field pulses. We show for core shifts beyond ~20-25% of the disk radius, the initial motion is characterized by distortions of the vortex, a transient cross-tie wall state, and instabilities in the core polarization that influence the core trajectories.

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X. M. Cheng, K. Buchanan, R. Divan, K. Y. Guslienko, D. J. Keavney. 2009-01-07. Non-linear vortex dynamics and transient effects in ferromagnetic disks. https://doi.org/10.1103/physrevb.79.172411

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