MAGNETORESISTANCE BEHAVIOR OF NI LAYER UNDER CU FILM

The weak-localization effect is very sensitive to the presence of magn etic moments. We use it to study the formation of localized moments in thin Ni layers under a 100 Cu film. The Ni thickness varies between 0 and 4 Angstrom. We measured the magnetoresistance (MR) of these sampl es at temperatures ranging from 0.4 to 21 K. The magnetic field with t he strength of up to 1 T, was applied normal to the film surface. We f ind that MR is more positive In samples with Ni underlayer than in Cu film. Comparing our results with the prediction of weak localization t heory, the magnetic moment is detected only in Ni underlayers thicker than 2 Angstrom.