Magnetization reversal in particulate L1₀ nanostructures

Authors

Jian Zhou, University of Nebraska - Lincoln
Ralph Skomski, University of Nebraska-LincolnFollow
Kory D. Sorge, University of Nebraska-LincolnFollow
David J. Sellmyer, University of Nebraska-LincolnFollow

Date of this Version

8-1-2005

Comments

Published in Scripta Materialia, Volume 53, Issue 4 , August 2005, Pages 453-456. doi:10.1016/j.scriptamat.2005.04.035 http://www.sciencedirect.com/science/journal/13596462 Copyright © 2005 Acta Materialia Inc. Published by Elsevier Ltd. on behalf of Acta Materialia Inc. Used by permission.

Abstract

Magnetization processes in particulate L1₀ FePt nanostructures are investigated by model calculations and numerical simulations. The systems considered include anisotropic nanograins embedded in non-magnetic matrix; randomly oriented nanoclusters embedded in a C matrix, and nanocomposites of FePt particles in a semi-hard matrix. The reversal mechanisms depend on both intra- and intergranular features. Quasi-coherent rotation dominates the reversal in weakly-coupled granular magnets, but interface imperfections yield a disproportionately strong coercivity reduction. Strong intergranular exchange leads to a transition to a discrete pinning regime, which is accompanied by a coercivity maximum.