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.
Mots-clés : micromagnetics, finite elements
@article{M2AN_2004__38_2_235_0,
author = {Alouges, Fran\c{c}ois and Conti, Sergio and DeSimone, Antonio and Pokern, Yvo},
title = {Energetics and switching of quasi-uniform states in small ferromagnetic particles},
journal = {ESAIM: Mod\'elisation math\'ematique et analyse num\'erique},
pages = {235--248},
publisher = {EDP-Sciences},
volume = {38},
number = {2},
year = {2004},
doi = {10.1051/m2an:2004011},
mrnumber = {2069145},
zbl = {1085.82015},
language = {en},
url = {http://www.numdam.org/articles/10.1051/m2an:2004011/}
}
TY - JOUR AU - Alouges, François AU - Conti, Sergio AU - DeSimone, Antonio AU - Pokern, Yvo TI - Energetics and switching of quasi-uniform states in small ferromagnetic particles JO - ESAIM: Modélisation mathématique et analyse numérique PY - 2004 SP - 235 EP - 248 VL - 38 IS - 2 PB - EDP-Sciences UR - http://www.numdam.org/articles/10.1051/m2an:2004011/ DO - 10.1051/m2an:2004011 LA - en ID - M2AN_2004__38_2_235_0 ER -
%0 Journal Article %A Alouges, François %A Conti, Sergio %A DeSimone, Antonio %A Pokern, Yvo %T Energetics and switching of quasi-uniform states in small ferromagnetic particles %J ESAIM: Modélisation mathématique et analyse numérique %D 2004 %P 235-248 %V 38 %N 2 %I EDP-Sciences %U http://www.numdam.org/articles/10.1051/m2an:2004011/ %R 10.1051/m2an:2004011 %G en %F 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: Modélisation mathématique et analyse numérique, Tome 38 (2004) no. 2, pp. 235-248. doi : 10.1051/m2an:2004011. http://www.numdam.org/articles/10.1051/m2an:2004011/
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