Optical and magneto-optical properties of Co/Pt multilayers

Optical and magneto-optical spectral properties have been studied both experimentally and theoretically for a series of Co/Pt multilayers. Diagonal and off-diagonal components of the optical conductivity tensor have been determined in the photon energy range 0.8-5.5 eV from the polar Kerr rotation and ellipticity and the ellipsometry measurements. On the basis of self-consistent spin-polarized relativistic linear muffin-tin orbital band-structure calculations within the local spin-density approximation the conductivity tensor has been evaluated and the role of the spin-orbit interaction and the induced polarization effect at the multilayer interface in the formation of the magneto-optical activity has been studied for various model Co-Pt multilayers and alloys. The relevance of the interface alloying effect for the explanation of the experimental results has been examined and discussed.