Highly coercive thin-film nanostructures

Authors

• Jian Zhou, University of Nebraska - Lincoln
• Ralph Skomski, University of Nebraska-LincolnFollow
• Arti Kashyap, University of Nebraska-LincolnFollow
• Kory D. Sorge, University of Nebraska-LincolnFollow
• Yucheng Sui, University of Nebraska-LincolnFollow
• Maria Daniil, University of Nebraska - LincolnFollow
• L. Gao, University of Nebraska - Lincoln
• M. L. Yan, University of Nebraska - Lincoln
• Sy_Hwang Liou, University of Nebraska-LincolnFollow
• Roger D. Kirby, University of Nebraska-LincolnFollow
• David J. Sellmyer, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

4-1-2005

Comments

Published in Journal of Magnetism and Magnetic Materials 290–291 (April 2005), pp. 227–230; in “Proceedings of the Joint European Magnetic Symposia” (JEMS’ 04), Edited by O. Gutfleisch, V.N. Narozhnyi, U. Nowak, T. Schrefl and M. Ziese.
Copyright © 2004 Elsevier B.V. Used by permission. doi:10.1016/j.jmmm.2004.11.189 http://www.elsevier.com/locate/jmmm

Abstract

The processing, structure, and magnetism of highly coercive Sm–Co and FePt thin-film nanostructures are investigated. The structures include 1:5 based Sm–Co–Cu–Ti magnets, particulate FePt:C thin films, and FePt nanotubes. As in other systems, the coercivity depends on texture and imperfections, but there are some additional features. A specific coercivity mechanism in particulate media is a discrete pinning mode intermediate between Stoner-Wohlfarth rotation and ordinary domain-wall pinning. This mechanism yields a coercivity maximum for intermediate intergranular exchange and explains the occurrence of coercivities of 5 T in particulate Sm–Co–Cu–Ti magnets.