Refractive indices of reactive magnetooptical thin films.
A method is described for determining the refractive indices of magnetooptical thin films. The films are deposited in a multilayer stack so that they can be protected from the environment. A thick, transparent substrate is used so that both air incident and substrate incident optical measurements can be performed. The normal incidence reflectance, transmittance, and magnetooptical rotation and ellipticity are used to compute the complex refractive index of the thin film. This technique is applied to a TbFe and a TbFeCo alloy. The addition of Co is found to significantly enhance the magnetooptic indices at long wavelengths.