Giant magnetoresistance dependence on the lateral correlation length of the interface roughness in magnetic superlattices

The giant magnetoresistance (GMR) observed in magnetic multilayers, is due to spin-dependent electron transport. In order to study the influence of the interface roughness on the spin-dependent scattering we produced epitaxial Fe/Cr(001) superlattices with negligible bulk scattering. The interface roughness was varied by carefully annealing the samples. The vertical and lateral interface roughness components were quantitatively determined by specular and diffuse synchrotron x-ray diffraction using anomalous scattering. We find that the magnitude of the GMR effect increases with decreasing lateral correlation length ${\xi }_x$ and increasing vertical roughness amplitude η.