Regensburg 2013 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DF: Fachverband Dielektrische Festkörper

DF 12: Poster 1

DF 12.48: Poster

Dienstag, 12. März 2013, 10:30–13:30, Poster D

First-principles study of the structural stability of Mn₃Z (Z=Ga, Sn and Ge) Heusler compounds — •D. Zhang¹, B. Yan^1,2, S.-C. Wu¹, J. Kuebler³, G. Kreiner¹, and C. Felser^1,2 — ¹Max Planck Institute for Chemical Physics of Solids, Dresden, Germany — ²Johannes Gutenberg-Universität Mainz, Staudingerweg 9, 55128 Mainz, Germany — ³Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany

We investigate the structural stability and magnetic properties of cubic, tetragonal and hexagonal phases of Mn₃Z (Z=Ga, Sn and Ge) Heusler compounds using the first-principles density-functional theory. We propose that the cubic phase plays an important role as an intermediate state in the phase transition from the hexagonal to the tetragonal phase. Consequently, Mn₃Ga and Mn₃Ge behave differently from Mn₃Sn, because the relative energies of the cubic and hexagonal phases are different. These results agree with experimental observations from these three compounds. The weak ferromagnetism of the hexagonal phase and the perpendicular magnetocrystalline anisotropy of the tetragonal phase obtained in our calculations are also consistent with experiment.