MAGNETOOPTICAL KERR-EFFECT IN FE-SIO2 GRANULAR FILMS

Polar Kerr rotation spectra of Fe-SiO2 granular films were measured at room temperature in the wavelength region between 400 nm and 850 nm. A maximum Kerr rotation angle (θk) of 18 min was obtained when a magnetic field of 10 kOe was applied perpendicular to the film plane. We have measured θk as a function of Fe volume fraction (f v) of the films. It was found that θk increases with increasing fv and peaks at fv≊0.4. We also found that θk decreases as the Fe particle size increases. Our results indicate that the density of Fe particles and the interfaces between Fe particles and SiO2 matrix may play an important role in the Kerr rotation of granular films. © 1995 American Institute of Physics.