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arXiv · 0705.1555

Effective anisotropy of thin nanomagnets: beyond the surface anisotropy approach

Jean-Guy Caputo·Yuri Gaididei·Volodymyr P. Kravchuk·Franz G. Mertens·Denis D. Sheka
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Abstract

We study the effective anisotropy induced in thin nanomagnets by the nonlocal demagnetization field (dipole-dipole interaction). Assuming a magnetization independent of the thickness coordinate, we reduce the energy to an inhomogeneneous onsite anisotropy. Vortex solutions exist and are ground states for this model. We illustrate our approach for a disk and a square geometry. In particular, we obtain good agreement between spin-lattice simulations with this effective anisotropy and micromagnetic simulations.

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Jean-Guy Caputo, Yuri Gaididei, Volodymyr P. Kravchuk, Franz G. Mertens, Denis D. Sheka. 2007-05-28. Effective anisotropy of thin nanomagnets: beyond the surface anisotropy approach. https://doi.org/10.1103/physrevb.76.174428

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