Hysteresis of granular FePt:Ag films with perpendicular anisotropy

M. L. Yan, R. Skomski, A. Kashyap, L. Gao, S. H. Liou, D. J. Sellmyer

Research output: Contribution to journalArticle

19 Scopus citations

Abstract

Intergranular interactions in nanostructured FePt:Ag thin films and their effect on magnetic hysteresis are investigated. The films, produced by multilayer deposition plus rapid thermal annealing, consist of FePt nanoparticles embedded in a silver matrix. They are investigated by magnetization measurements and magnetic force microscopy. Analytical model calculations, supported by micromagnetic simulations, are used to elucidate the relation between coercivity, hysteresis-loop slope, and spatial correlations during magnetization reversal. The analytical calculations yield simple expressions for the loop slope and the coercivity as a function of the intergranular exchange. Small intergranular exchange enhances the coercivity, but for strong exchange there is a self-energy cutoff, associated with the onset of cooperative reversal and preventing alpha from becoming negative.

Original languageEnglish (US)
Pages (from-to)2495-2497
Number of pages3
JournalIEEE Transactions on Magnetics
Volume40
Issue number4 II
DOIs
StatePublished - Jul 1 2004

    Fingerprint

Keywords

  • Anisotropy
  • Magnetic recording
  • Magnetization reversal

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

Cite this