Experimental and Theoretical In Situ Spectral Magneto-Ellipsometry Study of Layered Ferromagnetic Structures

A method for processing of in situ spectral magneto-ellipsometry data has been developed to analyze planar ferromagnetic nanostructures. A multilayer model containing a ferromagnetic layer with two interfaces, a nonferromagnetic buffer layer, and a nonferromagnetic substrate has been tested within a new approach to the interpretation of magnetic-field-modulated spectral ellipsometric measurements involving the magnetooptical Kerr effect in the transverse configuration. In particular, the effect of the thickness of the ferromagnetic layer on the results of magneto-ellipsometric measurements has been analyzed. The measurements have been performed with polycrystalline Fe films with different thicknesses on a nonferromagnetic SiO2/Si(100) surface. The diagonal and off-diagonal components of the complex dielectric tensor in the spectral range of 1.38–3.45 eV have been determined by processing spectral magneto-ellipsometric data. The results have been compared to the available data obtained by other authors and to the calculation of the dielectric tensor of Fe within the density functional theory.