Interfacial roughness of Fe–Cr GMR superlattices (abstract)

Fe–Cr superlattices exhibit giant magnetoresistance effect which can be utilized in magnetic recording heads. There are many studies indicating the role of the interfacial structure on the magnetoresistance effect. To elucidate this point we have performed x‐ray diffraction study of three [Fe(30 A)/Cr(12 A)]10 superlattices which had been sputtered in 4, 7, and 10 mTorr of Ar. We used position sensitive detector in horizontal setup to collect simultaneously specular scattering intensity (z component of the scattering vector Q perpendicular to the film) and off‐specular intensity with y parallel to the plane of the sample. This technique allows to evaluate interfacial roughness at various length scales. Short range roughness may be due to interdiffusion, while some medium range roughness is also present, and could have effects on transport phenomena. In conventional low angle diffraction analysis these contributions are intermixed. From the Fourier transform of the scattered intensity distribution in Qx−Qy...