Energetics and switching of quasi-uniform states in small ferromagnetic particles
ESAIM: Modélisation mathématique et analyse numérique, Volume 38 (2004) no. 2, pp. 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: 10.1051/m2an:2004011
Classification: 65L60, 78M10, 82D40
Keywords: micromagnetics, finite elements
     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/}
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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
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VL  - 38
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PB  - EDP-Sciences
UR  - http://www.numdam.org/articles/10.1051/m2an:2004011/
DO  - 10.1051/m2an:2004011
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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, Volume 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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