Limitations of the two-media approach in calculating magneto-optical properties of layered systems

It is shown that in polar geometry and normal incidence the 2x2 matrix technique - as discussed in detail in a preceeding paper [Phys. Rev. B 65, 144448 (2002)] - accounts correctly for multiple reflections and optical interferences, and reduces only in the case of a periodic sequence of identical layers to the Fresnel formula of reflectivity, which in turn is the theoretical basis of the two-media approach, widely used in the literature to compute magneto-optical Kerr spectra. As a numerical example ab-initio calculations of the optical constants for an fcc Pt semi-infinite bulk using the spin-polarized relativistic screened Korringa-Kohn-Rostoker method show very good agreement with experimental data.Comment: 16 pages (LaTeX), 4 figures (Encapsulated PostScript), appears in Phys. Rev. B 66, 1744XX (2002

Modeling the optical constants of solids using acceptance-probability-controlled simulated annealing with an adaptive move generation procedure

The acceptance-probability-controlled simulated annealing with an adaptive move generation procedure, an optimization technique derived from the simulated annealing algorithm, is presented. The adaptive move generation procedure was compared against the random move generation procedure on seven multiminima test functions, as well as on the synthetic data, resembling the optical constants of a metal. In all cases the algorithm proved to have faster convergence and superior escaping from local minima. This algorithm was then applied to fit the model dielectric function to data for platinum and aluminum