Magnetization Reversal Mechanism of Co-Cr Perpendicular Magnetic Recording Media

In order to investigate the mechanism of magnetization reversal in Co-Cr perpendicular recording media, the angular dependence of the hysteresis loss was investigated. For a double-layer medium consisting of a Co-Cr layer and a Permalloy backing layer, it is easy to show that rotational magnetization reversal occurs in the Co-Cr layer. Judging from both the angular dependences of H
c
and of the hysteresis loss, the initial growth layer and the columnar structure layer in Co-Cr sputtered film were found to undergo magnetization reversal by domain wall motion and by rotation, respectively. Other Co-Cr films with different M
s
and H
c
values were also studied with respect to the prevailing mechanism of magnetization reversal.