Precise noise characterization of perpendicular recording media

Akihiko Takeo, Yuka Takahashi, Yoichiro Tanaka, Kenji Miura, Hiroaki Muraoka, Yoshihisa Nakamura

Research output: Contribution to journalConference articlepeer-review

18 Citations (Scopus)


Perpendicular recording is one of the technology candidates to extend the areal density growth trend with the superior thermal stability and the high recording resolution. As we have experienced with longitudinal recording, noise originating from perpendicular recording also has a strong impact on the channel performance. In this study, the noise characteristics of the readout waveforms of a tri-layer perpendicular media1 and single-pole write/MR read heads were investigated using precise time-domain analysis. Waveform fluctuations were obtained by subtracting the ensemble-averaged signal from each measured noise-contaminated waveform. The time-domain analysis makes clear the dominant type of transition-related noise such as transition jitter, pulse breathing or dc noise, etc. It was revealed that the noise from perpendicularly recording medium concentrates at the center of written transitions. The dominant transition noise source was found to be the transition position jitter. The level of transition jitter of the perpendicular media used in this study was found to be comparable to that of 5 Gbpsi class longitudinal media. MFM measurements revealed that magnetization fluctuates in large size of about 80 nm, which results in the fluctuation of the transition centerline. Reducing transition jitter should be the focus of developing future high performance perpendicular recording media.

Original languageEnglish
Pages (from-to)4987-4989
Number of pages3
JournalJournal of Applied Physics
Issue number9 II
Publication statusPublished - 2000 May
Event44th Annual Conference on Magnetism and Magnetic Materials - San Jose, CA, United States
Duration: 1999 Nov 151999 Nov 18


Dive into the research topics of 'Precise noise characterization of perpendicular recording media'. Together they form a unique fingerprint.

Cite this