Dresden 2011 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 9: Magnetic Materials I
MA 9.2: Vortrag
Montag, 14. März 2011, 15:00–15:15, HSZ 401
Magnetism of quaternary Heusler alloys — •Josef Kudrnovsky1, Shyamal Bose2, Ilja Turek3, and Vaclav Drchal1 — 1Institute of Physics AS CR, Prague — 2Brock University, St. Catharines — 3Institute of Physics of Materials AS CR, Brno
The electronic properties, exchange interactions, finite-temperature magnetism and transport properties of random Ni2MnSn quaternary Heusler alloys doped with Cu- and Pd-atoms are studied theoretically by means of first-principles calculations over the entire concentration range. While the magnetic moments are only weakly dependent on the alloy composition, the Curie temperatures exhibit strongly non-linear behavior with respect to Cu-doping in contrast with an almost linear concentration dependence in the case of Pd-doping. The residual resitivity obey the Nordheim rule while the dominating contribution to the temperature-dependent resistivity is due to thermodynamical fluctuations originating from the spin-disorder, which, according to our calculations, can be described reasonably well via the disordered local moments model. The present parameter-free theory agrees qualitatively and also reasonably well quantitatively with all available experiments.