THE EFFECTS OF THE INTERFACIAL STRUCTURES ON MAGNETORESISTANCE IN METALLIC SUPERLATTICES

The effects of interfacial structures on the electronic transport prop erties in layered structures are investigated within the framework of the coherent potential approximation. In this paper, the two types of interfacial structures between a magnetic slat, and a non-magnetic sla b are assumed to exist in the superlattice. The first one, named the f lat interface, is that the average distribution number of magnetic ion s is nearly constant through the interfacial layers. The second, named the diffused interface, is that the average distribution number of ma gnetic ions decreases gradually in interfacial layers from the magneti c slab to the non-magnetic dab. It is shown within the framework of th e mean field approximation that for the resistance the flat interface always shows larger absolute values than the diffused interface and th at for the magnetoresistance ratio the value of it depends on the rela tive position of electron energy levels of magnetic and non-magnetic i ons. Making a comparison between the experimental and calculational re sults, we can say that the spinflop scattering of conduction electrons due to the isolated localized spins is expected to play a major role in the case of the diffused interface where the superlattice shows the large magnetoresistance ratio.