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Ultrafast Vortex-Core Reversal Dynamics in Ferromagnetic Nanodots

Ki-Suk Lee·Konstantin Y. Guslienko·Jun-Young Lee·Sang-Koog Kim
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Abstract

To verify the exact underlying mechanism of ultrafast vortex-core reversal as well as the vortex state stability we conducted numerical calculations of the dynamic evolution of magnetic vortices in Permalloy cylindrical nanodots under an oscillating in-plane magnetic field over a wide range of the frequency and amplitude. The calculated results reveal different kinds of the non-trivial dynamic responses of vortices to the driving external field. In particular, the results offer insight into the 10 ps scale underlying physics of the ulrafast vortex-core reversals driven by small amplitude (~10 Oe) in-plane fields. This work also provides fundamentals of how to manipulate effectively the dynamical switching of the vortex-core orientation.

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Ki-Suk Lee, Konstantin Y. Guslienko, Jun-Young Lee, Sang-Koog Kim. 2007-03-21. Ultrafast Vortex-Core Reversal Dynamics in Ferromagnetic Nanodots. https://doi.org/10.1103/physrevb.76.174410

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