Computer Simulation of Magnetization Reversal Mechanisms of Hexagonal Platelet Particle: Effect of Material Parameters

The effect of material parameters on the switching mechanism and switching field, H sw , of hexagonal platelet particles was investigated by computer simulation. The field H E was applied perpendicular to the platelet plane which is the easy axis direction of the platelet. The magnetic moments of platelets with a small exchange stiffness constant, A , switch in the normal vortex mode; those of particles with a large A switch in the quasi-coherent rotation mode. The magnetic moments of platelets with a small uniaxial anisotropy constant, K u , reverse in the normal vortex mode; platelets with a large K u reverse in the crater mode. The magnetic moments of a thin platelet switch in the quasi-coherent rotation mode; a thick platelet switches in the normal vortex mode.