Magnetic and electrical transport properties of electrodeposited Ni-Cu alloys and multilayers

Electrodeposited Ni-Cu alloys and nanoscale Ni-Cu/Cu multilayers were produced by direct-current plating and pulse-plating, respectively. The room-temperature electrical resistivity and thermopower as well as the Curie temperature for the Ni-Cu electrodeposits were in good agreement with relevant data reported for metallurgically processed Ni-Cu alloys. The same parameters were investigated also for the multilayers as a function of the constituent magnetic and non-magnetic layer thicknesses. The electrical resistivity of the multilayers was much larger than calculated for a parallel resistance model and their thermopower was more negative than expected on the basis of a volume average model, by using bulk values of both parameters for the sublayer materials. These differences were ascribed to surface scattering processes which can be significant in nanoscale multilayer structures.