P10

Characterization of the surface electronic, magnetic and dynamical properties of new materials with high spin polarization (Cinchetti / Aeschlimann)

This project deals with the study and characterization of new materials with high spin polarization by the use of two highly complementary experimental techniques: spin- and time resolved photoemission and the time-resolved magneto-optical Kerr effect. Spin-resolved photoemission has a unique ability to directly access the electron spin polarization at the surface region, this quantity being the most important parameter for device applications. The photoemission measurements will be used to systematically develop sophisticated sample specific surface preparation procedures with the aim of reaching the highest possible surface spin polarization. To achieve values very close to 100% spin polarization, these optimized procedures will be combined with an active tailoring of the surface achieved using specific surface terminations with different materials (such as Al, Fe, Co, and others, depending on the particular alloy under investigation) and keV ion bombardment. Besides investigating the static surface properties, we also plan to extend our studies into the time domain to investigate the ultra fast spin-dependent electron dynamics. These studies will provide unique information about the fundamental interactions governing spin dynamics in half-metallic ferromagnets as a prerequisite for building optimized devices for spintronics applications.
All studies will be performed on thin films provided by projects P 2 (Jakob), P 11 (Jourdan), and P 12 (Ando).