Two interacting cubic particles: effect of placement on switching field and magnetisation reversal mechanism

The Landau-Lifshitz-Gilbert equation has been solved for two interacting particles in which each particle was divided into large number of elements, so that a detailed investigation of the effect of interparticle interactions on the magnetisation reversal mechanisms of these particles could be investigated. Interparticle interactions were found to have a drastic effect on the switching field. Positive interactions were observed when the particles were separated in the z direction. The reversal mechanisms for the isolated particle and the positively interacting pair were very similar, despite a large difference in switching field. When the particles were displaced in the x direction, the switching field of the interacting pair was reduced from that of the isolated particle. The reversal mechanism for this particle configuration was very complex and asymmetric, due to the nonuniformity of the interaction field. An interesting feature was observed when the particles were separated in the x and z directions. The switching field for this arrangement was lower than that of the isolated particle, indicating a net negative interaction effect