Parts | Days | Selection | Search | Downloads | Help
MA: Fachverband Magnetismus
MA 13: Poster Ia: Electron Theory (1); Magnetic Imaging (2,3); Thin Films (4-25); MSMA (26-33); Magn. Semiconductors (34-42); Magn. Half Metals and Oxides (43-60)
MA 13.16: Poster
Tuesday, March 24, 2009, 10:15–13:00, P1A
Magnetic and structural properties of epitaxial thin films of the Heusler compounds Cu2MnAl and Co2MnGe — •Denise Erb, Jörg Dudek, Frank Brüssing, Gregor Nowak, Kurt Westerholt, and Hartmut Zabel — Ruhr-Universität Bochum Experimentalphysik IV / Festkörperphysik, Bochum, Deutschland
Several Heusler compounds possess half metallic properties in the ordered L21 structure, which make them promising candidates for spintronic applications. We have grown thin films of the Heusler phases Co2MnGe and Cu2MnAl using ion beam sputtering and UHV magnetron sputtering on MgO(100) and sapphire a-plane substrates. The structural properties were studied by x-ray diffraction and x-ray reflectivity. Epitaxial thin films with smooth surfaces can be prepared with the substrates at room temperature. The Co2MnGe film prepared on Al2O3 a-plane and a 2nm V seed layer exhibits 12 well defined peaks in the in-plane rocking scan of the (022)-Bragg reflection, indicative of the growth of 3 different crystalline domains rotated by 30∘ relative to each other. The Heusler phase Cu2MnAl is actually not half metallic, but exhibits model type behaviour concerning the relations between the structural and magnetic properties. It can be grown on MgO(001) with the in-plane [100]-direction rotated by 45∘ from the MgO [100]-direction. In the as-grown state the Cu2MnAl film is non magnetic, ferromagnetic order starts developing when annealing above 280∘C. The increasing ferromagnetic magnetization is accompanied by an increasing intensity of the (002) superstructure Bragg reflection.
The authors thank the DFG for financial support within the SFB 491.