Based on Luttinger’s formulation the complex optical conductivity tensor is calculated within the framework of the spin-polarized relativistic screened Korringa-Kohn-Rostoker method for layered systems by means of a contour integration technique. For polar geometry and normal incidence, ab initio Kerr spectra of multilayer systems are then obtained by including via a $2\times 2$ matrix technique all multiple reflections between layers and optical interferences in the layers. Applications to $\mathrm{Co}/{\mathrm{Pt}}_5$ and ${\mathrm{Pt}}_3/\mathrm{Co}/{\mathrm{Pt}}_5$ on the top of a semi-infinite fcc(111) Pt bulk substrate show a good qualitative agreement with the experimental spectra, but differ from those obtained by applying the commonly used two-media approach.

• Received 27 November 2001

DOI:https://doi.org/10.1103/PhysRevB.65.144448