Alors que l'auto-organisation est un domaine maintenant consacré pour les semi-conducteurs, il est en émergence pour les matériaux magnétiques, avec une activité soutenue les cinq dernières années. Un panorama des contributions de l'auto-organisation au magnétisme est proposé ici, avec pour but de montrer les possibilités nouvelles offertes, notamment par rapport à la lithographie. Une première catégorie d'études concerne la mesure et la compréhension de phénomènes magnétiques en basse dimensionnalité, qui existent dans les matériaux applicatifs mais ne peuvent y être étudiés quantitativement du fait de leur complexité : mise en ordre magnétique, anisotropie magnétique, superparamagnétisme. Une seconde catégorie concerne la perspective de l'utilisation directe de systèmes auto-organisés. Des exemples sont donnés pour combattre le superparamagnétisme en fabriquant des structures auto-organisées épaisses, ou établir des fonctionnalités nouvelles, notamment le contrôle de l'anisotropie et de la dispersion de propriétés.
Self-organization of magnetic materials is an emerging and active field. An overview of the use of self-organization for magnetic purposes is given, with a view to illustrate aspects that cannot be covered by lithography. A first set of issues concerns the quantitative study of low-dimensional magnetic phenomena (1D and 0D). Such effects also occur in microstructured and lithographically-patterned materials but cannot be studied in these because of the complexity of such materials. This includes magnetic ordering, magnetic anisotropy and superparamagnetism. A second set of issues concerns the possibility to directly use self-organization in devices. Two sets of examples are given: first, how superparamagnetism can be fought by fabricating thick self-organized structures, and second, what new or improved functionalities can be expected from self-organized magnetic systems, like the tailoring of magnetic anisotropy or controlled dispersion of properties.
Mot clés : Auto-organisation, Auto-assemblage, Magnétisme, Anisotropie magnétique, Micromagnétisme, Superparamagnétisme
Olivier Fruchart 1
@article{CRPHYS_2005__6_1_61_0, author = {Olivier Fruchart}, title = {Epitaxial self-organization: from surfaces to magnetic materials}, journal = {Comptes Rendus. Physique}, pages = {61--73}, publisher = {Elsevier}, volume = {6}, number = {1}, year = {2005}, doi = {10.1016/j.crhy.2004.11.007}, language = {en}, }
Olivier Fruchart. Epitaxial self-organization: from surfaces to magnetic materials. Comptes Rendus. Physique, Volume 6 (2005) no. 1, pp. 61-73. doi : 10.1016/j.crhy.2004.11.007. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2004.11.007/
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