On One of the Possible Mechanisms of Formation of Induced Anisotropy in Ferromagnetic Films

With the assumption that the concentration of nonmagnetic inclusions (lattice defects, impurity atoms, oxides) is higher at the grain boundary than inside the grain, a steady state distribution of inclusions is determined along the grain boundary in a ferromagnetic film. It appears to be nonuniform since inclusions leave those boundary sections where the jump of the normal component of magnetization at the boundary is maximum and go into sections where the jump is minimum. Nonuniformity of the inclusion distribution at the boundary results in a magnetic anisotropy. Expressions are derived for the anisotropy energy. The numerical evaluation shows that the experimental value of anisotropy energy is obtained by such a mechanism in the case when inclusions decrease strongly the magnetization of the boundaries.