Controlling magnetic and transport properties of granular alloys through Joule heating

Melt-spun Cu–Co ribbons are annealed by linearly varying current Joule heating. During the annealing, the electrical resistance is measured in order to follow the structural transformations within the samples. The resistance versus current curves show a characteristic behavior for all samples studied. This fact is used to specify optimum conditions to obtain the best nanostructure which displays the maximum giant magnetoresistance ratio.