Magnetic anisotropy derived from interparticle interactions in CoPtCr/SiO2 granular thin film longitudinal media

Abstract

High field ferromagnetic resonance measurements of the anisotropy field of longitudinal recording thin-film media Magnetic and structural properties of hexagonal-close-packed-CoCrPt-C granular media for high areal density recordingThe magnetic anisotropy derived from interparticle interactions in a CoPtCr/SiO 2 granular thin film longitudinal medium has been experimentally studied. In order to clarify the effect of magnetostatic interactions between particles in the medium, the angular dependence of the interaction fields has been investigated. The interaction fields in the medium were obtained from the remanent magnetization curves measured in several directions in the plane normal to the medium plane by compensating for the demagnetizing fields at each measurement direction. It has been shown that the interparticle interactions in the medium exhibit clear anisotropy, which is related to the magnetostatic interactions. As a result, the intrinsic magnetic anisotropy of the medium has been quantitatively separated into two contributions, the magnetic interaction anisotropy between particles and the anisotropy of each particle. The magnetic anisotropy caused by the interparticle interactions in the medium plays an important role in the thermal stability of the magnetization in the recorded media, in the minor-loop magnetizing process and in the recording process of the medium when using a ring-type head.