CO CU MULTILAYERS STUDIED BY USING THE SN-119 PROBE/

To observe spin polarization in nonmagnetic layers sandwiched by magne tic layers, Sn-119 Mossbauer spectra of [Co(20 Angstrom)/Cu(20 - x Ang strom)/Sn-119(1.5 Angstrom)/Cu(x Angstrom)] (x = 0, 5 and 10) multilay ers were measured. A magnetic fraction is observed in every spectrum, and the average hyperfine field ($) over bar H-f at Sn nuclei in a Cu layer changes from 14 kOe (x = 0) to 8 kOe (x = 10). It was also obser ved that the polarization is greatly reduced by adding a Cr layer of o nly 2 Angstrom to the Co/Cu interfaces. The spectrum of the x = 10 fil m, measured under an external field of 30 kOe, cannot be interpreted w ithout assuming magnetic fractions both in parallel and antiparallel t o the external field, which indicates an oscillation of spin polarizat ion in a Cu layer.