Magnetization reversal in high anisotropy multi-domain particles

Abstract

The magnetization reversal process in small spherical particles with strong uniaxial magneto-crystalline anisotropy is examined theoretically for the special case of a particle containing three domains separated by two parallel plane boundaries. The widths of the domain boundaries are assumed to be small compared with the critical size for single domain behaviour. Choice of a nucleation criterion, which satisfies the available experimental data for the dependence of coercivity on particle size, is shown to lead to theoretical hysteresis loops which compare favourably with recently reported experimental results for MnGa particles.