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arXiv · 1004.2689

Ground-state configurations in ferromagnetic nanotori

Vagson L. Carvalho-Santos·Winder A. Moura-Melo·Afranio R. Pereira
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Abstract

Magnetization ground states are studied in toroidal nanomagnets. The energetics associated to the ferromagnetic, vortex and onion-like configurations are explicitly computed. The analysis reveals that the vortex appears to be the most prominent of such states, minimizing total energy in every torus with internal radius $r\gtrsim10\,{\rm nm}$ (for Permalloy). For $r\lesssim10\,{\rm nm}$ the vortex remains the most favorable pattern whenever $R/\ell_{ex}\gtrsim1.5$ ($R$ is the torus external radius and $\ell_{ex}$ is the exchange length), being substituted by the ferromagnetic state whenever $R/\ell_{ex}\lesssim1.5$.

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Vagson L. Carvalho-Santos, Winder A. Moura-Melo, Afranio R. Pereira. 2010-04-15. Ground-state configurations in ferromagnetic nanotori. https://doi.org/10.1063/1.3487924

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