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Granular CoxC1-x and (Co/Pt)xC1-x thin films with different metal-volume fractions x are prepared by simultanious electron beam evaporation of Co or CoPt and C targets. The films are condensed on NaCl- and quartz substrates. The structure of the films is controlled by choosing different substrate temperatures Ts in the range between 20°C and 350°C as well as by annealing the thin film samples after generation at temperatures Ta between 200°C and 700°C. The structural properties of the films are examined by means of transmission electron microscopy and electron diffraction. Electrical resistivity of the films is measured in the temperature range between T = 4.2K and T = 300K. In order to reveal the magnetic properties of the granular thin films a SQUID magnetometer is used. In addition to the measurement of hysteresis loops at T = 4.2K and T = 300K, remanent magnetisation curves are measured in order to examine the magnetic coupling between the particles of the granular films. Additionally magnetoresistance measurements are performed at T = 4.2K.

In the present treatise magnetic and magneto-optic properties of Fe/Tb multilayers are investigated using Kerr spectroscopy, SQUID and Torque magnetometry in order to clarifiy the influence of interfaces on the magnetization reversal and the origin of the magnetic perpendicular anisotropy (PMA). The torque curves evidence different mechanisms to induce the PMA, viz., formation of alloy at rough Fe-on-Tb interfaces and antiferromagnetic coupling between Fe and Tb moments at smooth Tb-on-Fe interfaces. In addition, the observed magnetic cone structure is confirmed by model calculations based on the model due to Stoner and Wohlfarth. Different Fe modifications as isolated amorphous Fe, FeTb alloy and bulk amorphous Fe are identified on inspection of the polar Kerr curves. According to the Kerr spectra, the contribution of amorphous Fe in multilayers increases with increasing number of a-Fe/Tb bilayers.