Magnetization reversal mechanism of Co–O films with oblique anisotropy

Abstract

The angular dependence of the coercivity Hc for vacuum evaporated Co–O films with oblique anisotropy is studied both in an in-plane and in a normal plane in order to clarify the magnetization reversal mechanism. The angular dependence of Hc in the in-plane is remarkably different from that in the normal plane. The Co–O films have columnar structure, and the columnar grains look almost the same in both planes. The anisotropy field Hk in the normal plane is much higher than in the in-plane. Simulated curves of the angular dependence of Hc using the curling incoherent magnetization reversal model on the basis of measured values for Hc of the easy axis direction and Hk are similar to the experimental results in both planes. These results indicate that the magnetization reversal mechanism of the Co–O films is the incoherent rotation and that the interaction among the grains is different in both planes.

Metal Evaporated Media

“…Such variation with a steep increase of the switching field close to the hard axis direction is typical of nonuniform reversal process, such as Kondorsky type (Kondorsky, 1937), curling (Aharoni, 1966;Frei et al, 1957), or fanning (chain of spheres) (Aharoni, 1966). The reversal mode of the magnetic subunits has therefore been discussed with reference to these models (Richter, 1993a;Speliotis and Judge, 1991;Sugita et al, 1999;Victora, 1987;Wierenga et al, 2000).…”