変動成分抽出法を用いた二層膜媒体におけるスパイクのマッピング(磁気記録)

概要

論文の詳細を見る
Spike noise of double-layered perpendicular magnetic recording media with exchange-biased soft-magnetic underlayers (SULs) was studied on the basis of readback signals from a GMR head. By obtaining their averaged wave form and standard deviation, readback signals were classified into two groups: signals from the hard magnetic component and signals from the soft magnetic component. No spike was observed when the SUL retained a single domain condition: either (1) no magnetic field was applied, or (2) an external magnetic field less than the bias field was applied to the easy axis of the SUL. When an external magnetic field greater than the bias field was applied to the easy axis of the SUL, the domain wall caused spike noise with a width of a few micrometers. When an external magnetic field was applied to the hard axis of the SUL, single-peak pulses with a width of about 200 nm were observed. Since these pulses were distributed randomly in the media and the pulse density increased with increasing magnetic field, they probably originated from ripples in the SUL.
2006-03-01