Effect of crystalline disorder on magnetic switching in small magnetic cells

I present a study of the influence of disorder in thin magnetic films on the switching behavior of small magnetic cells of well-defined shape and size. The disorder considered arises from randomly oriented crystalline grains of different shape, size, and crystalline orientation which gives rise to locally fluctuating intrinsic anisotropy directions and strengths. The study comprises a theoretical investigation of a disordered Stoner-Wohlfarth model, as well as micromagnetic simulations. I show that the fluctuations in the total anisotropy and therefore in the switching fields are controlled by a single dimensionless parameter. The theoretical findings are well confirmed by micromagnetic simulations of many different samples. (C) 2002 Elsevier Science B.V. All rights reserved.