Department Spin and Topology in Quantum Materials

Spin-Polarization analysis in Heusler alloys

The Heusler compound Co2FeSi is a promising material for magneto-electronic devices. With a Curie temperature of 1100K and a saturation magnetization of 6 Bohr magnetons and a high spin polarization at the Fermi edge it fulfils the essential requirements for magnetic sensors or spin valve structures. An essential feature for such devices is the micro-magnetic domain structure. X-ray magnetic circular dichroism–photo emission electron microscopy has been used for a direct observation of the domain structure of single- and polycrystalline samples. Spin polarized photo emission from a single domain of the single crystal shows a spin polarization of 16% at the Fermi energy and up to 35% in the d-bands, at room temperature.

_{A. Gloskovskii, J. Barth, B. Balke, G.H. Fecher, C. Felser, F. Kronast, R. Ovsyannikov, H. Dürr, W. Eberhard and G. Schönhense.
J. Phys. D: Appl. Phys. 40 (2007) 1570–1575}