Interlayer exchange coupling mediated by valence-band electrons

Abstract

The interlayer exchange coupling mediated by valence-band electrons in all-semiconductor IV-VI magnetic/nonmagnetic superlattices is studied theoretically. A three-dimensional tight-binding model, accounting for the band and magnetic structure of the constituent superlattice components is used to calculate the spin-dependent part of the total electronic energy. The antiferromagnetic coupling between ferromagnetic layers in EuS/PbS superlattices is obtained, in agreement with the experimental evidences. The results obtained for the coupling between antiferromagnetic layers in EuTe/PbTe superlattices are also presented.