GIANT MAGNETORESISTANCE IN SPINODALLY DECOMPOSED CU-NI-FE FILMS

We report the observation of the GMR effect in spinodally decomposed Cu-20Ni-20Fe thin films. A ΔR/R value as high as 6.5% was observed at room temperature. In contrast to the commonly observed temperature-dependent behavior of ΔR/R increasing at low temperature; thin film shows a decrease in ΔR/R at 4.2 K. The dependence of the GMR effect on various deposition parameters, such as substrate temperature has been studied. The observed giant magnetoresistance behavior in Cu-20Ni-20Fe films is most likely related to the field-induced decrease in electron scattering in a pseudosuperparamagnetic material, as well as the spin-dependent scattering at the two-phase interface and in the ferromagnetic phase.