Magneto-optical properties of nanocomposites (Co41Fe39B20)х(SiO2)100-х

Abstract

Magneto-optics properties of (Co41Fe39B20)x(SiO2)100−x alloys were studied applying both experimental spectral ellipsometry and quantum mechanical theory (incl. molecular calculus) approaches. Magneto-optics (MO) properties of the alloys were derived from the measured parameters of reflected elliptically polarized light. The experimental data were explained applying selection rules for the magnetic quantum number. Theoretical approach based on electron gas in a metal with angular momentum coupled to magnetic field demonstrated applicability of the magnetic quantum number and Hund’s rule for ascertaining the MO alloys properties. In this modeling, the magneto-optics properties of ferromagnetic alloys can be explained being based on derivations for the magnetic quantum number selection rules. Hund’s rule directly influences the dielectric tensor off-diagonal elements signs. The nonrelativistic Schrödinger equation for the Co2Fe2B alloy was numerically solved taking into account spins of Co and Fe atoms as well as orbital moments of wave functions in order to check the theoretical approach. As a result, the MO dispersion curves can be theoretically evaluated using the modified Spicer ratio that includes density of states functions with specific azimuthal and spin quantum numbers.

Keywords

• cobalt iron boron alloy
• modified spicer ratio
• molecular calculus
• hund’s rule