A simulation of rotation magnetization processes in longitudinal thin-film media

The effect of the local demagnetizing field on the rotation magnetization processes in Co-based alloy longitudinal thin-film media was studied as a simple approach to understanding the correlation between the medium coercivity and the strength of the in-plane easy axis crystallographic texture. The rotation magnetization of a single domain particle with uniaxial anisotropy in a thin film was simulated without and with the effect of a uniform local demagnetizing field. Longitudinal thin-film media were then modeled as assemblies of non-interacting single domain particles with various easy axis distributions, and the demagnetizing field was found to decrease the in-plane coercivity as the easy axes of an increasing fraction of the grains are tilted out of the film plane. The rotational hysteresis remains a valid method of measuring the anisotropy field after considering the demagnetizing effect.