THE ROLE OF THE MAGNETIC-STRUCTURE AND INTERFACE SCATTERING IN THE GMR OF MAGNETIC MULTILAYERS

Room temperature giant magnetoresistance (GMR) has been investigated f or Co/Cu(1 1 1) multilayers grown by DC magnetron sputtering. The effe ct of annealing on the magnetic structure of multilayers with a nomina l copper thickness of 0.9 nm has been studied, a strong linear correla tion between the GMR and the volume fraction of ferromagnetic regions is observed. Such behaviour has been used to elucidate the scattering mechanism responsible for the GMR of this system, and suggests that s- d scattering into the split d-band of cobalt is the dominant mechanism responsible for the GMR of Co/Cu multilayers. This is in contrast to systems like Fe/Cr where experimental studies on the effect of interfa cial mixing indicate that interfacial scattering resulting from spin-d ependent interface potentials contributes strongly to the observed GMR .