Ferromagnet-semiconductor hybrid structures: Hall devices and tunnel junctions

For spintronics, both, the properties of small ferromagnetic particles as well as the properties of ferromagnet-semiconductor hybrid structures are of importance. Below we describe how micro-Hall magnetometry provides information about the magnetisation switching of small ferromagnetic particles. In the second part we demonstrate spin dependent transport through thin GaAs membranes. The latter experiments point to the important role of spin-flip scattering in ferromagnet-semiconductor hybrid structures.