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Mesoscopic bound on anisotropy in itinerant ferromagnets

Piet W. Brouwer·Denis A. Gorokhov
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Abstract

We calculate the anisotropy energy of a single-domain ferromagnetic particle in which the only source of anisotropy is the presence of non-magnetic impurities. We find that such anisotropy takes the form of combined easy-axis and easy-plane anisotropies, with random orientations of the axes. Typically the anisotropy energy is of order $N^{1/2} \hbar/tau_{so}$, where $N$ is the number of electrons in the ferromagnetic particle and $τ_{so}$ is the spin-orbit time.

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Piet W. Brouwer, Denis A. Gorokhov. 2004-12-17. Mesoscopic bound on anisotropy in itinerant ferromagnets. https://doi.org/10.1103/physrevlett.95.017202

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