Fast and Slow Magnetization Processes in Magnetic Recording Media

Fast and Slow Magnetization Processes in Magnetic Recording Media

Information loss due to thermal activation is a major concern in ultrahigh-density magnetic recording media. The usually considered mechanism is thermally activated magnetization reversal over micromagnetic energy barriers. However, micromagnetic approaches ignore local anisotropy fluctuations, which translate into a time-dependent reduction of the remanent magnetization. The effect is negligib...

Recording Processes in Perpendicular Patterned Media Using Longitudinal Magnetic Recording Heads

Experimental study of the recording processes in patterned magnetic media is presented. The reading of patterned media using spin-valve elements is compared to the signal levels from magneto-resistive sensors. Writing and reading of patterned columnar media at high areal densities is demonstrated. A new experimental technique has been developed that allows precise determination of the location ...

Recording performances in perpendicular magnetic patterned media

We report on the recording performances and signal-to-noise ratio analyses of perpendicular magnetic bit-patterned media. Two different types of magnetic samples are investigated. They differ by the way that they were patterned (nano-imprint versus e-beam lithography) as well as their magnetic properties (Co/Pt multilayers and CoCrPt alloy are the recording layers). By using a contact read/writ...

Magnetic structures in Co-Cr media for perpendicular magnetic recording

High bit densities have been demonstrated in longitudinal as well as in perpendicular magnetic recording. For the latter an area density of more than 12 G b i t / i n 2 has been obtained in a sputtered C o C r T a hard disk with a soft magnetic underlayer recorded with a special single pole head. In this paper the role of microstructure and morphology in relation to the compositional separation...

Magnetic interactions in CoCrPt-oxide based perpendicular magnetic recording media