Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9834522 | Journal of Magnetism and Magnetic Materials | 2005 | 5 Pages |
Abstract
The recording characteristics dependence on the intermediate layer (IL) thickness is investigated for CoPtCr-SiO2 double-layered perpendicular media, which contain antiferromagnetically coupled layers (AFM) formed below soft-magnetic underlayer (SUL). With the decrease of the IL thickness from 20 to 10Â nm, the signal-to-media-noise ratio (S/Nm) is slightly improved. The normalized media noise (Nm/Siso) is nearly identical although the magnetic properties, such as a coercivity, gradually deteriorate. We have calculated the bit patterns at a 480Â kFCI recording density using the Landau-Lifshitz-Gilbert (LLG) micromagnetic model and found that the S/Nm gain per IL thickness (â¼0.1Â dB/nm) can be expected if the magnetic properties are kept the same. Adding AFM layers reduces the spike noise dramatically. The media noise at high densities, beyond the saturation (â¼1000Â kFCI), is 24% smaller for media having AFM layers than that of conventional-type SUL. The writing field required for suppressing the noise appearing at a low frequency is also reduced for media with AFM-SUL. Interestingly, the thermal stability of a medium with AFM-SUL is improved with a decrease in IL thickness and is â0.01Â dB/decade for IL=10Â nm even for a 10-nm-thick recording layer.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Kazumasa Shimoda, Toshio Sugimoto, Ryosaku Inamura, Takenori Ohshima, Daiju Kaneko, Sanae Takefusa, Takuya Uzumaki, Atsushi Tanaka,