Pseudohelicoidal Surface Spin Waves

Abstract

A simple theoretical semiclassical calculation of the surface ferromagnetic equilibrium is given. The equilibrium orientation of the magnetization in the layers which are near the surface is tilted from the direction of the magnetization in the bulk. This rotation depends on both surface and bulk anisotropies. Thus, some instabilities in the spectrum disappear, and optical surface spin waves are found to be less energetic than what is usually calculated. Moreover, a simple interpretation of a possible origin of the pinning of surface spins is given.