Ferromagnet/Semiconductor Hybrid Structures
The integration of ferromagnetism into semiconductor devices is a focus of worldwide research because of the promising aspect of utilizing the electron spin for logic operations in spin- and magnetoelectronics (spintronics).
Aim of this Core Research Area
This core research area is devoted to investigations of hybrid structures consisting of ferromagnetic metals and semiconductors and all-semiconducting structures containing dilute magnetic semiconductors, which are expected to yield a highly spin-polarized current in the semiconductor and/or exhibit a high tunneling magneto-resistance in magnetic-tunneling-junction geometries.
Spin injection: Mechanisms and spin alignment
The generation of spin-polarized electrons by electrical injection (spin injection) from ferromagnetic materials into semiconductors is an essential prerequisite for the realization of a whole class of spintronic devices. We aim to clarify and utilize the mechanisms involved in spin injection into semiconductors as well as in spin relaxation, spin transport, and spin alignment in semiconductors. This research is used to derive concepts for highly efficient spin injection in spintronic devices.
With regard to potential applications, important criteria for the selection of ferromagnetic materials are a high Curie temperature above room temperature, a large spin polarization of free electrons, a sufficient thermal stability, and the compatibility with semiconductor substrates regarding lattice match or lattice mismatch accommodation. In this respect, ferromagnetic metals or half-metals and large-bandgap dilute magnetic semiconductors are of particular interest. We aim at a comprehensive understanding of the structure and magnetic properties of ferromagnetic films grown on III-V semiconductors.
