GIANT MAGNETORESISTANCE WITH LOW SATURATION FIELD IN (NIXCO100-X/CU) MULTILAYERS

We have investigated giant magnetoresistance (GMR) in NixCo100-x/Cu multilayers for x in the range 20-100. The GMR at room temperature is greater than 12% for magnetic alloys with x near 80, where the magnetocrystalline anisotropy is small. The smallest saturation fields are found near x = 60 in the region where the magnetostriction vanishes. This combination of large GMR and small saturation field results in large MR field sensitivities up to 0.16%/Oe at room temperature. In order to maximize these parameters, we have also studied the dependence of the MR on the magnetic layer thickness and the number of bilayers.