Magnetism in reduced dimensions

Olivier Fruchart; André Thiaville

doi:10.1016/j.crhy.2005.10.011

Magnetism in reduced dimensions

Olivier Fruchart ¹ ; André Thiaville ²

¹ Laboratoire Louis-Néel (CNRS), 25, avenue des Martyrs, BP166, 38042 Grenoble cedex 9, France
² Laboratoire de physique des solides, université Paris-Sud, bâtiment 510, 91405 Orsay cedex, France

Comptes Rendus. Physique, Spintronics, Volume 6 (2005) no. 9, pp. 921-933.

Abstract
Résumé

We propose a short overview of a few selected issues of magnetism in reduced dimensions, which are the most relevant to set the background for more specialized contributions to the present Special Issue. Magnetic anisotropy in reduced dimensions is discussed first, on a theoretical basis, then with experimental reports and views from surface to single-atom anisotropy. Then, conventional magnetization states are reviewed, including macrospins, single domains, multidomains, and domain walls in stripes. Dipolar coupling is examined for lateral interactions in arrays, and for interlayer interactions in films and dots. Finally thermally-assisted magnetization reversal and superparamagnetism are presented. For each topic we have sought a balance between well established knowledge and recent developments.

Nous proposons un panorama de quelques aspects du magnétisme en dimensions réduites, appropriés comme toile de fond pour les articles plus spécialisés de ce numéro spécial. L'anisotropie magnétique en dimensions réduites est discutée, sur le plan théorique, puis appuyée par des exemples, allant des surfaces aux atomes individuels. Les configurations d'aimantation les plus courantes sont ensuite décrites : macrospins, monodomaines, multidomaines, parois dans des bandes. Les couplages magnétiques, essentiellement dipolaires, sont décrit pour des réseaux et pour des bi-couches. Enfin nous présentons les effets de l'activation thermique, de la baisse de coercitivité jusqu'au superparamagnétisme. Pour chaque aspect nous avons recherché un équilibre entre résultats établis et développements récents.

Published online: 2005-11-01

DOI: 10.1016/j.crhy.2005.10.011

Keywords: Nanomagnetism, Micromagnetism, Magnetic anisotropy, Superparamagnetism, Reduced dimensions
Mots-clés : Nanomagnétisme, Micromagnétisme, Anisotropie magnétique, Superparamagnétisme, Dimension réduite

Author's affiliations:

Olivier Fruchart ¹; André Thiaville ²

¹ Laboratoire Louis-Néel (CNRS), 25, avenue des Martyrs, BP166, 38042 Grenoble cedex 9, France
² Laboratoire de physique des solides, université Paris-Sud, bâtiment 510, 91405 Orsay cedex, France

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Olivier Fruchart; André Thiaville. Magnetism in reduced dimensions. Comptes Rendus. Physique, Spintronics, Volume 6 (2005) no. 9, pp. 921-933. doi : 10.1016/j.crhy.2005.10.011. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2005.10.011/

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