MODEL CALCULATION OF MAGNETIC SURFACE-STATES IN MULTILAYER SYSTEMS

Influence of the perpendicular magnetism on the electronic structure o f multilayer systems at surfaces and interfaces is investigated in det ail by analytical Green function calculations for the one-dimensional semi-infinite chain. The existence and position of spin-polarized surf ace states, even present in antiferromagnetically coupled systems, is derived explicitely. These slates can be ultimately prescribed to mult ilayer systems with antiferromagnetical interlayer coupling, or more g enerally, to systems involving a ferromagnetic-non-ferromagnetic inter face. The existence of spin-polarized surface states, the energetic po sitions of which are shown to be linearly dependent on the magnitude o f the surface magnetic moment, is predicted practically for each symme try type. Analytical considerations are confirmed by numerical calcula tions within the tight-binding Green function renormalization method.