Quantitative study of the interdependence of interface structure and giant magnetoresistance in polycrystalline Fe/Cr superlattices

We present a quantitative characterization of the interface roughness of Fe/Cr superlattices based on specular and off-specular x-ray diffraction using anomalous scattering, We discuss the dependence of the amplitude of the giant magnetoresistance (GMR) effect, including changes in the interlayer magnetic coupling, on the interface structure. We observe a reduction of the GMR effect with increasing amplitude of the interface roughness having constant lateral correlation length. However, the physical interpretation of this clear result in terms of spin-dependent interface scattering remains unclear because of the unknown bulk contribution.