Anisotropy dispersion in (CoCrPt)1-x(SiO2)x perpendicular recording media

A. Carter, L. E. Fernandez-Outon, Y. Inaba, S. J. Greaves, H. Muraoka, K. O'Grady

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)


The distribution of easy axis orientation in perpendicular media is of technological importance because it affects the value of S* (see Fig. 1), which quantifies the switching field distribution (SFD) and hence partially determines the data density achievable on a given medium. The distribution is controlled by the crystallographic orientation of grains and factors such as intergranular exchange and dipolar coupling. Due to strong demagnetising fields in the perpendicular orientation, traditional measurements of remanence as a function of angle are difficult to interpret and have required the use of large-scale computational models. In this work we have utilised the variation of coercivity HC with angle, which has the advantage that at HC the global demagnetising field is zero. Additionally, since such materials follow essentially the Stoner-Wohlfarth mode of reversal, the variation of HC with angle, HC(θ), is much greater than that for the remanence. We find that for (CoCrPt)1-x(SiO2)x, where the level of exchange coupling is controlled, the distribution of magnetic easy axes is narrower when the exchange coupling is reduced, but dipolar coupling between the grains is strong and affects the magnetisation reversal significantly.

Original languageEnglish
Pages (from-to)2269-2272
Number of pages4
JournalJournal of Magnetism and Magnetic Materials
Issue number18
Publication statusPublished - 2008 Sept


  • Anisotropy dispersion
  • Demagnetising field
  • Dipolar coupling
  • Exchange coupling
  • Perpendicular medium
  • Switching field distribution

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics


Dive into the research topics of 'Anisotropy dispersion in (CoCrPt)1-x(SiO2)x perpendicular recording media'. Together they form a unique fingerprint.

Cite this