Simulation of the recording process on Co-Cr layers with a VSM

To investigate the role of both perpendicular and in-plane head field components in the recording process, a ring head writing transition in Co-Cr layers was simulated with a vibrating sample magnetometer by changing the field strength and rotating the sample simultaneously. The magnetization components parallel and perpendicular to the field direction were measured. An increase in perpendicular magnetization, which can be larger than 50% at the center of the transition, and a decrease in in-plane magnetization were found in the case where the head field was switched compared to the case where the head field was not switched. These effects decrease with increasing maximum field values and with decreasing effective perpendicular anisotropy of the layer. The in-plane field component appears to play an important role: without this component, these effects were not observed. The results are consistent with recording experiments with ring heads and prove that the extra minima in the frequency response described in an earlier paper have a micromagnetic origin