Approach to high-density recording using CGC structure

Junichi Yasumori, Yoshiaki Sonobe, Simon J. Greaves, Kim Kong Tham

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)


Coupled granular/continuous (CGC) perpendicular media with two different continuous layers, a Co/Pd multilayer and a CoCrPtB cap layer, were compared. It was confirmed that both thickness optimized layers functioned well as exchange coupled continuous layers. A LandauLifshitzGilbert simulation was performed for various grain boundary thicknesses, and the signal-to-noise ratio improvement predicted by the simulation was in good agreement with experiments. The CGC structure was susceptible to side erasure on account of its StonerWohlfarth type magnetic switching, and the recording performance was dominated by the granular layer. Controlling this behavior would enable further improvement in recording density. The benefits of discrete-track media with the CGC structure are discussed. We found that ion irradiation of the CGC media could be effective to create soft magnetic regions in between recorded tracks, which act as guard bands, improving the recording performance.

Original languageEnglish
Article number4782099
Pages (from-to)850-855
Number of pages6
JournalIEEE Transactions on Magnetics
Issue number2
Publication statusPublished - 2009 Feb


  • Discrete-track medium
  • Exchange coupling
  • Soft guard band
  • Track edge noise


Dive into the research topics of 'Approach to high-density recording using CGC structure'. Together they form a unique fingerprint.

Cite this