TRANSVERSE SUSCEPTIBILITY OF PARTICULATE RECORDING MEDIA IN DIFFERENT REMANENCE STATES

Transverse susceptibility measurements were performed on isotropic and aligned γ-Fe2O3 and ZnTi-doped barium-ferrite powder samples in different remanence states. Measurement results obtained on a sintered NdFeB sample are given for comparison. Deviations of the experimental result from the Stoner-Wohlfarth theory are ascribed to inhomogeneous magnetization states and particle-particle interactions. The remanent reversible transverse susceptibility appears to be much more sensitive to these influences than standard remanence-curve analysis and thus provides a new experimental approach to the interaction problem. © 1995 American Institute of Physics.