P11

Preparation and investigation of interfaces of Heusler thin films (Jourdan)

We plan to investigate and control the electronic properties of surfaces and interfaces of Heusler materials. The main objective is to understand how the crystallographic orientation and the termination of the surfaces of Heusler compounds influence the spin polarization, magnetization and electronic density of states.

The investigations will be performed on sputter deposited high quality epitaxial thin films starting with the experimentally well controlled Heusler compound Co₂Cr_0.6Fe_0.4Al and focusing on novel materials at a later stage. The thin film orientation will be controlled by employing different substrate materials; the surface termination will be modified by dusting and monolayer deposition in an MBE system (surface engineering).

For the investigation of the local spin polarization at the interfaces, spectroscopy of excitations and the study of band structure effects tunneling spectroscopy on planar junctions will be applied. Depth profiles of the magnetization close to the interfaces will be obtained by polarized neutron reflectometry.

Within the research group projects P 5 (Elmers), P 7 (Felser / Schönhense), P 9 (Hamrle / Hillebrands), and P 10 (Cinchetti / Aeschlimann) complementary interface related investigations will be performed on our samples.