Lichtstreuung an Spinwellen dünner ferromagnetischer Schichten und heterogener Doppelschichten

In this thesis the method of Brillouinscattering from spinwaves is used to investigate the magnetic properties of thin ferromagnetic films and heterogeneous doublelayers. Our films and filmsystems, consisting of iron, nickel and permalloy, are evaporated onto sapphire and silicon substrates. The magnetic parameters saturation magnetization J$_{o}$, exchange constante A and o the gyromagnetic ratio g, are determined from measurements of the dispersion of the spinwaveenergies as a function of the filmthickness, which is typically varied between 5 and 100 nm. We examined the coupling of the surfacemodes of two ferromagnetic layers, separated by a non-magnetic spacerlayer. Two properties of light-scattering from spinwaves in very thin films (d $\le$ 10 nm), which are due to the scattering mechanism itself are also investigated. This is an asymmetry in the ratio of the intensities of Stokes and anti-Stokes scattering down to filmthicknesses of some nanometers and an increase of the scattering intensity upon decreasing filmthickness. The latter appears for suitable combinations of film and substrate materials. The maximum of the intensity versus thickness curve peaks at about 5 nm