Improvement of signal to noise ratio for Co/Pd multilayer perpendicular magnetic recording media by the addition of an underlayer

T. Onoue, T. Asahi, K. Kuramochi, J. Kawaji, T. Homma, T. Osaka

Research output: Contribution to journalConference article

9 Citations (Scopus)


Signal and noise characteristics of Co/Pd multilayer perpendicular magnetic recording media are discussed based upon MFM analysis. The noise of the Co/Pd multilayer media is originated mainly from irregularities in the magnetic transition regions, and can be drastically suppressed by increasing the thickness of the carbon underlayer although a large number of reversed magnetic domains between the magnetic transitions still exist. The fine magnetic clusters formed in the medium with a thick carbon underlayer result in clear magnetic transition boundaries of recorded bits in the high recording density region. By examining the profile of the M-H loops, the decrement in the α value, which is defined as the slope of M-H loop at the value of coercivity, improves the signal to noise (S/N) ratio for the Co/Pd multilayer media.

Original languageEnglish
Pages (from-to)40-44
Number of pages5
JournalJournal of Magnetism and Magnetic Materials
Issue number1-3
Publication statusPublished - 2001 Oct 1
EventProceedings of the 5th Perpendicular Magnetic Recording Conference (PMRC 2000) - Sendai, Japan
Duration: 2000 Oct 232000 Oct 26



  • Amorphous carbon underlayer
  • Multilayers
  • Perpendicular magnetic recording

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

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