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Energetics and switching of quasi-uniform states in small ferromagnetic particles

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Alouges, François, Conti, Sergio, DeSimone, Antonio and Pokern, Yvo. (2004) Energetics and switching of quasi-uniform states in small ferromagnetic particles. ESAIM: Mathematical Modelling and Numerical Analysis, Vol.38 (No.2). pp. 235-248. ISSN 0764-583X

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Official URL: http://dx.doi.org/10.1051/m2an:2004011

Abstract

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.

Item Type:	Journal Article
Subjects:	Q Science > QA Mathematics Q Science > QC Physics
Divisions:	Faculty of Science > Mathematics
Library of Congress Subject Headings (LCSH):	Ferromagnetism -- Mathematical models, Finite element method
Journal or Publication Title:	ESAIM: Mathematical Modelling and Numerical Analysis
Publisher:	EDP Sciences
ISSN:	0764-583X
Date:	2004
Volume:	Vol.38
Number:	No.2
Page Range:	pp. 235-248
Identification Number:	10.1051/m2an:2004011
Status:	Peer Reviewed
Access rights to Published version:	Open Access
Funder:	European Union (EU), Deutsche Forschungsgemeinschaft (DFG)
Grant number:	FMRX-CT98-0229 (EU)
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URI:	http://wrap.warwick.ac.uk/id/eprint/3825