Distribution in strength of the particle anisotropies in a ferromagnetic aggregate

H. P. Goeckner, I. M. Obaidat, J. S. Kouvel

Research output: Contribution to journalArticlepeer-review


A particle anisotropy distribution in a ferromagnetic aggregate is explored via the effects of transverse magnetic fields (H) on a remanent magnetization (MR) previously established. Pertinent to this unconventional property, we have extended the Stoner-Wohlfarth model for a ferromagnetic aggregate of single-domain particles with randomly oriented anisotropy axes. If all the particle anisotropies are identical in strength, it is predicted that the magnetization normal to H stays nearly constant at MR as H is raised up to a critical value and then drops very rapidly as H is raised further. Deviations from this sharp behavior can be readily interpreted in terms of a spread in the size of the particle anisotropies. Thus, from experimental data on a commercial magnetic-memory material, it is deduced that the anisotropy spread is nonzero but fairly narrow. However, the narrowness of this deduced effect may result in part from interparticle exchange coupling, which is ignored in the model.

Original languageEnglish
Pages (from-to)413-417
Number of pages5
JournalJournal of Magnetism and Magnetic Materials
Issue number3
Publication statusPublished - Aug 2002
Externally publishedYes


  • Extended Stoner-Wohlfarth model
  • Magnetic-memory floppy disk
  • Particle anisotropy distribution
  • Remanent magnetizationin transverse fields

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics


Dive into the research topics of 'Distribution in strength of the particle anisotropies in a ferromagnetic aggregate'. Together they form a unique fingerprint.

Cite this