Dynamics of a nanoparticle as a one-spin system and beyond

H. Kachkachi

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Dynamics of a nanoparticle as a one-spin system and beyond

H. Kachkachi

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Abstract

We review some recent results beyond the now established theory of magnetization switching of a nanoparticle within the single-spin approximation. The first extension is that of the Stoner-Wohlfarth model for magnetization static switching under applied magnetic field including the effect of temperature at long-time scales. The second concerns a generalization of the Néel-Brown model for thermoactivated dynamic magnetization switching to include the effect of exchange interaction in the framework of Langer's theory in the intermediate-to-high damping limit. We finally argue why the single-spin approximation is not appropriate for very small nanoparticles.

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H. Kachkachi. 2003-07-18. Dynamics of a nanoparticle as a one-spin system and beyond. https://arxiv.org/abs/cond-mat/0307457

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