Energetics and switching of quasi-uniform states in small ferromagnetic particles
ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Volume 38 (2004) no. 2, p. 235-248

We present a numerical algorithm to solve the micromagnetic equations based on tangential-plane minimization for the magnetization update and a homothethic-layer decomposition of outer space for the computation of the demagnetization field. As a first application, detailed results on the flower-vortex transition in the cube of Micromagnetic Standard Problem number 3 are obtained, which confirm, with a different method, those already present in the literature, and validate our method and code. We then turn to switching of small cubic or almost-cubic particles, in the single-domain limit. Our data show systematic deviations from the Stoner-Wohlfarth model due to the non-ellipsoidal shape of the particle, and in particular a non-monotone dependence on the particle size.

DOI : https://doi.org/10.1051/m2an:2004011
Classification:  65L60,  78M10,  82D40
Keywords: micromagnetics, finite elements
@article{M2AN_2004__38_2_235_0,
author = {Alouges, Fran\c cois and Conti, Sergio and DeSimone, Antonio and Pokern, Yvo},
title = {Energetics and switching of quasi-uniform states in small ferromagnetic particles},
journal = {ESAIM: Mathematical Modelling and Numerical Analysis - Mod\'elisation Math\'ematique et Analyse Num\'erique},
publisher = {EDP-Sciences},
volume = {38},
number = {2},
year = {2004},
pages = {235-248},
doi = {10.1051/m2an:2004011},
zbl = {1085.82015},
mrnumber = {2069145},
language = {en},
url = {http://www.numdam.org/item/M2AN_2004__38_2_235_0}
}

Alouges, François; Conti, Sergio; DeSimone, Antonio; Pokern, Yvo. Energetics and switching of quasi-uniform states in small ferromagnetic particles. ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Volume 38 (2004) no. 2, pp. 235-248. doi : 10.1051/m2an:2004011. http://www.numdam.org/item/M2AN_2004__38_2_235_0/

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