Abstract
Optical and magneto-optical properties of FexO1-x (x>0.5) oxide-metal composite films were measured in photon energy range from 1.5eV to 4eV by ellipsometry and polar Kerr effect. The observed complex reflectivity ratio Rp/Rs were compared with those calculated from anisotropic effective dielectric constant by a model that fine Fe metallic ellipsoids are precipitated in dielectric matrix (FeO). Volume fractions of metallic phase thus obtained are in good agreement with those from magnetization measurement, but depolarization factor of metallic precipitates does not explain the perpendicular magnetic anisotropy of the films. Kerr rotation angle, θk, increases linealy with average magnetization of the composite films up to 20 min for σg=100 emu/g at photon energy 2eV. The ratio θk/ σg is twice as large as that for pure Fe.