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It is shown that the spin polarization direction of the reflected electrons on Fe(001) strongly changes with minute amounts of MgO. Our ab initio electronic band structure and spin-dependent electron reflection calculations reveal that the MgO-induced out-of-plane relaxation of the Fe surface layer is responsible for this behavior. Our study points toward the subtle feature that the major change of the spin-dependent electron reflection properties of the Fe(001) surface is already caused by the very first MgO coverage.

We report on spin-polarized electron reflection experiments in which the electron-spin motion is studied in spin-dependent quantum-well structures. Quantum-well state induced oscillations of both the electron reflectivity and the electron-spin motion are observed in the system $\mathrm{Au}∕\mathrm{Co}(001)$ as a function of the Au overlayer thickness. A Fabry-P\'erot interferometer model can explain the main features of the experimental data. We discuss the influence of the spin-dependent reflectivity, the inelastic mean free path, the diffusively scattered electron intensity contribution, and the growth mode on the behavior of the electron-spin motion within the interferometer model.

The evolution of magnetic configurations inside ferromagnetic ${\mathrm{Fe}}_{30}{\mathrm{Au}}_{70}/{\mathrm{Fe}}_{65}{\mathrm{Au}}_{35}$ bilayers have been studied. The two FeAu alloys magnetization are ferromagnetically exchange coupled at the interface and both exhibit an in-plane uniaxial anisotropy. The magnetization reversal of a bilayer from one saturated state to the other occurs via an interface domain wall state, which is metastable. This interface magnetic domain wall which spreads mainly in the soft ${\mathrm{Fe}}_{30}{\mathrm{Au}}_{70}$ layer is pinned at the interface by the harder ${\mathrm{Fe}}_{65}{\mathrm{Au}}_{35}$ alloy. Its presence and its ``compression'' are evidenced by magnetization, electrical transport, and ac-susceptibility measurements combined with a unidimensional micromagnetic calculation. In order to investigate magnetization reversal dynamics, temperature dependence as well as magnetic aftereffect measurements were performed. The magnetization reversal process is found to be thermally activated and activation parameters could be deduced.