GIANT MAGNETORESISTANCE, ANTIFERROMAGNETIC VOLUME FRACTION AND SATURATION FIELD IN CO CU MULTILAYERS/

A series of Co/Cu multilayers was prepared exhibiting the giant magnet oresistance in the first maximum of the oscillatory exchange coupling 'regime. The size of the magnetoresistance strongly depends on the thi ckness of the layers involved, the substrate material, the buffer laye r and the sputtering conditions. The analysis of resistive and magneti c data reveals that to a first approximation the magnetoresistance lin early depends on the volume fraction of Co coupled antiferromagnetical ly. This volume fraction can be derived from the extrapolated remanent magnetization. It is investigated under which conditions and to what extent the linearity applies. A maximum of the magnetoresistivity of 7 2 % at room temperature was reached under optimized conditions.