Giant magnetoresistance of electrodeposited Ni81Cu19/Cu multilayers

The room-temperature magnetoresistance (MR) characteristics were investigated for electrodeposited Ni 81 Cu 19 /Cu multilayers as a function of the constituent magnetic and nonmagnetic layer thicknesses. The maximum giant magnetoresistance (GMR) was obtained around 3 nm magnetic layer thickness and 1 nm nonmagnetic layer thickness. For multilayers with GMR behavior, especially around the optimum sublayer thickness combination, the MR curves could he considered as consisting of a low-field (H I kOe) contribution. The latter contribution can he ascribed to chemical intermixing at the interfaces between the magnetic and nonmagnetic layers due to an exchange reaction between Cu and Ni. We have identified two factors that may significantly influence the GMR of electrodeposited multilayers: (i) the position and orientation of the investigated sample section on the cathode surface during deposition and (ii) the deterioration of the particular citrate/sulfate bath used.