Quantum-Size-Induced Oscillations of the Electron-Spin Motion in Cu Films on Co(001)

We report on spin-polarized electron reflection experiments in which the electron-spin motion is studied in spin-dependent quantum well structures. Oscillations of the electron-spin motion due to quantum interference are observed in the model system $\mathrm{Cu}/\mathrm{Co}(001)$ both as a function of electron energy and Cu overlayer thickness. The reflectivity as well as the spin-motion data can be well interpreted in terms of a Fabry-Pérot interferometer model. In particular, this opens the possibility of studying the spin-dependent reflection properties of the buried $\mathrm{Cu}/\mathrm{Co}$ interface.