GIANT MAGNETORESISTANCE EFFECT OBSERVED IN FE MO SUPERLATTICES FORMEDBY MAGNETRON SPUTTERING/

Since the giant magnetoresistance (GMR) effect was found in an Fe/Cr s uperlattice in 1988, metallic multilayers containing magnetic layers s eparated by a nonmagnetic spacer have been the subject of extensive st udy. The GMR effect is observed in most 3d-element systems, such as Fe /Cr multilayers. We have prepared Fe/Mo multilayers, a 4d-element syst em, by magnetron sputtering. The GMR effect has been found in samples with antiferromagnetic interlayer coupling. The magnetoresistance (MR) ratio exceeds 12% at 4.2 K, and an oscillatory behaviour with respect to the Mo spacer layer thickness has been found. The oscillation peri od is about 1.0-1.2 nm, which is consistent with previously reported K err effect studies. These results suggest that relatively rough interf aces and moderately thin iron layer thicknesses will increase the GMR of the system.