MAGNETIC AND MAGNETOOPTICAL POLAR KERR SPECTRA STUDIES IN NI AU MULTILAYERS/

Magnetic, magneto-optical (MO) and X-ray diffraction studies on Ni/Au multilayers deposited by e-beam evaporation onto glass substrates are reported. The individual layer thickness t(Ni) varied between 0.6 and 2.7 nm and t(Au) was fixed at 1.5 nm. The magnetic measurements at 5 K show negative surface anisotropy and the absence of a dead layer. The most prominent feature in the MO polar Kerr spectra is a negative pea k at 2.7 eV. The MO spectra are well explained by the theory using the bulk Ni and Au optical and MO data. The modelling indicates that the optical constants of Au change when the Au layer becomes ultrathin.