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The structural properties and magnetic anisotropy of Pt/Co/Pt trilayers grown on thermally oxidized (Si/SiO2) and naturally oxidized silicon (Si/Siox) are presented. Although similar substrates and identical preparation conditions are used distinct differences in the structural composition are found which stem from the Pt seed layer created via ion assisted sputtering. While for thermal oxidized Si a Pt/Co/Pt trilayer is formed, for systems grown on naturally oxidized Si a complex PtSi alloy formation within the seed layer is observed as a consequence of the high ion energies of ion assisted sputtering. The composition of the PtSi alloy varies along the growth direction with a low Si content at the interface to Co and the lattice constant is similar to bulk Pt. The latter provides a much higher magnetic interface anisotropy constant compared to Pt/Co/Pt on thermal oxidized Si of about 0.9 mJ/m2 which is comparable to the highest values found for MBE grown Co on single crystalline Pt(111).

The influence of the substrate temperature on the growth of highly textured Ni(111) and epitaxial Ni(200) with the relationships Ni[100]∥Si[110] and Ni(001)∥Si(001) on hydrogen terminated Si(100) wafer substrates by means of direct current magnetron sputtering is reported. In order to minimize crystal defect formation and to achieve a high quality epitaxial growth of Ni on Si, a two step deposition process was developed whereby different deposition conditions were used for an initial nickel seed layer and the remaining nickel film. The in-plane and out-of-plane structural properties of the films were investigated using x-ray scattering techniques, whereas magneto-optical Kerr effect and neutron reflectometry were used to confirm the magnetic nature of the epitaxially deposited nickel films.

The dispersion of spin wave modes which due to the dipolar interactions propagate along different directions of ordered superlattices of nanospheres is investigated. For this purpose a procedure similar to the well-known method of linear combination of atomic orbitals is applied. Different geometries of two-dimensional (triangular and square) and three-dimensional (simple cubic and hexagonal-close-packed) arrangements are considered and the influence of dimensionality on the spin wave dynamics is analyzed. A phase transition which is caused by the competition between dipolar and uniaxial anisotropy interactions is predicted by the investigation of the dispersion of the uniform Kittel mode for the superlattice of the hexagonal order. In conclusion, it is shown how the weak dipolar interaction enhances or decreases the relaxation time in the samples with a controlled direction of the easy axis.