Abstract
Electrodeposited cobalt-silver heterogeneous films with giant magnetoresistance prepared by means of pulse technique have been investigated. The size distribution indicates that films are composed of superparamagnetic particles; however, ferromagnetic cobalt granules are also present. Magnetic and magnetotransport measurements support the presence of both kinds of particles. Structural analysis of the Co-Ag granular films revealed the presence of fcc-Ag and a mixture of hcp-Co and fcc-Co. No signs of solid solution were detected. GMR values up to 7% were measured at room temperature for the as-deposited films. High superparamagnetic contribution was observed in all conditions analyzed after the decomposition of the total magnetoresistance into its superparamagnetic and ferromagnetic contribution. © 2010 American Chemical Society.