MAGNETIZATION PROCESSES AND FERROMAGNETIC-RESONANCE OF HI-8 RECORDINGMEDIA

Investigations on ME videotape with tilted crystal and shape symmetry axes by means of ferromagnetic resonance (FMR) and transverse suscepti bility can be used to describe the out-of-plane magnetization process by the model of a single-domain particle with an extrinsic easy axis b etween the preferential axes of shape and crystal anisotropy. In this case, the effective anisotropy field strength is not a simple superpos ition of the terms determining the tape demagnetization and the crysta l anisotropy. Analysis of the stiffness conditions for the ferromagnet ic precession motion this ansatz leads to a necessary correction for t he calculation of the eigenfrequencies compared to the usual single-do main theory of the FMR. This general description can be transferred to the results of longitudinal and perpendicular recording media, as wel l as to single-domain particles with non-tilted axes. Beside theoretic al results, the paper also reports FMR investigations on several recor ding media.