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arXiv · 1102.0519

Normal modes of coupled vortex gyration in two spatially separated magnetic nanodisks

Ki-Suk Lee·Hyunsung Jung·Dong-Soo Han·Sang-Koog Kim
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Abstract

We found from analytical derivations and micromagnetic numerical simulations that there exist two distinct normal modes in apparently complex vortex gyrotropic motions in two dipolar-coupled magnetic nanodisks. The normal modes have characteristic higher and lower single angular eigenfrequencies with their own elliptical orbits elongated along the x (bonding axis) and y axes, respectively. The superposition of the two normal modes results in coupled vortex gyrations, which depend on the relative vortex-state configuration in a pair of dipolar-coupled disks. This normal-mode representation is a simple means of understanding the observed complex vortex gyrations in two or more dipolar-interacting disks of various vortex-state configurations.

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Ki-Suk Lee, Hyunsung Jung, Dong-Soo Han, Sang-Koog Kim. 2011-02-02. Normal modes of coupled vortex gyration in two spatially separated magnetic nanodisks. https://doi.org/10.1063/1.3662923

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