COMPLEX MAGNETOOPTICAL KERR ROTATION OF FE,FECO CU MULTILAYER FILMS/

The complex magneto-optical Kerr rotation spectra of Fe/Cu and FeCo/Cu bilayers and compositionally modulated films (CMF) were studied exper imentally and theoretically. In the bilayers, an enhancement of Kerr e llipticity epsilon(k) by a factor of 5 was observed at long wavelength side, while the Kerr rotation theta(k) can only be enhanced by a fact or of 2 around the plasma edge of Cu. In the CMFs, epsilon(k) was enha nced by 60% but no theta(k) enhancement was observed. Theoretical anal yses showed that both the magnitude of effective epsilon(xye) and the magnitude and signs of effective A(e) and B(e) are important for magne to-optical enhancement.