On the Angular Dependence of the Effective Spin‐Pinning in Thin Insulator Film

The angular dependence of the boundary conditions in a perfectly homogeneous insulator film with an uniaxial surface anisotropy is discussed with respect to the determination of the critical angle. The existence of two different critical angles and two different surface modes for each symmetry (symmetrical and antisymmetrical with respect to the central plane of the film) follows from this treatment for high negative values of the surface anisotropy constant K s .