Effects of nonuniform substitution on the reversal process of individual barium ferrite recording particles

Micromagnetic simulation is utilized to investigate the mechanism responsible for the sharp decrease with increasing particle size in the switching field observed from experimental measurements of isolated BaFe/sub 12-x/(CoTi)/sub x/O/sub 19/ particles. Simulation results show that nucleation can occur at applied field values far below the intrinsic anisotropy field when the effect of nonuniform substitution of Co-Ti is considered. >