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arXiv · 1610.05109

Controlling energy transfer time between two coupled magnetic vortex-state disks

H. Vigo-Cotrina·A. P. Guimarães
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Abstract

The influence of the in-plane uniaxial anisotropy (IPUA) in the mutual energy transfer time ($τ$) between two identical coupled nanodisks was studied. Using an analytical dipolar model we obtained the interactions between the disks along x and y directions (the coupling integrals) as a function of the uniaxial anisotropy constant (K$_σ$) and the distance. We find that the IPUA increases the interaction between the disks allowing shorter energy transfer times. For our range of K$_σ$ values we get a drop in the values of $τ$ of up to about 70$\%$. From the lagrangian of the system we obtained the equations of motion and the coupling frequencies of the dynamic system as a function of distance and K$_σ$. The coupling frequencies were also obtained from micromagnetic simulations. Our results of the simulations are in agreement with the analytical results.

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H. Vigo-Cotrina, A. P. Guimarães. 2016-10-17. Controlling energy transfer time between two coupled magnetic vortex-state disks. https://doi.org/10.1063/1.4971342

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