Dresden 2011 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 58: Spintronics II (jointly with TT, HL)
MA 58.8: Vortrag
Donnerstag, 17. März 2011, 19:00–19:15, HSZ 401
Spin relaxation by impurity scattering in metallic systems — Swantje Heers, •Phivos Mavropoulos, Rudolf Zeller, and Stefan Blügel — Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52425 Jülich
We present calculated results on spin relaxation in Cu, Ag and Au due to scattering at non-magnetic impurities of the 4th, 5th and 6th row of the periodic table (3d up to 6sp elements). We consider the processes of spin-flip scattering by spin-orbit coupling (SOC) at the impurity as well as SOC at the host atoms (Elliott-Yafet mechanism). Our results show that the SOC in the host is not so important in Cu, especially for heavy impurities with strong SOC, while it is essential in Au. In our approach we employ the full-potential Korringa-Kohn-Rostoker Green-function method (KKR) for the calculation of the electronic structure and the spin-flip transition probability Pkk′ss′, with s being the spin-index. A Fermi-surface integral of P over k and k′ yields then the spin-relaxation rate 1/τss′.
In order to go beyond the approximation of independent scattering events, implied by this approach, we calculate the scattering by impurity dimers at increasing distance from nearest to third-nearest neighbours. In this way we simulate possible effects of impurity clustering in the sample, caused e.g. by impurity attraction or increasing concentration. We find that the presence of nearest-neighbour dimers has a considerable effect on τss′, while the results for dimers with distance beyond second-nearest neighbours are practically the same as in the independent scattering approximation.