Micromagnetic predictions for magnetization reversal in CoNi films

Abstract

A dynamic, micromagnetic theory which includes domain nucleation, incoherent rotation of magnetization within grains, and complete magnetostatic interactions is described in detail. All significant input is derived from experimental data; the precise values of several other input variables, such as exchange constant and damping parameter, are found to be largely irrelevant. Preliminary calculations, which may be compared to measured hysteresis loops, are used to establish the considerable quantitative accuracy of the theory. The remaining calculations make predictions for unmeasured properties such as crystalline anisotropy and domain-wall motion. A substantial prediction of the paper is that it is possible for obliquely deposited CoNi films to have no zig-zag domain walls; however, a finite transition width owing to the incline of the CoNi grains is predicted to occur.