DPG Phi
Verhandlungen
Verhandlungen
DPG

Dresden 2006 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

DY: Dynamik und Statistische Physik

DY 50: Lattice Dynamics and Non-Linear Excitations

DY 50.3: Talk

Friday, March 31, 2006, 10:45–11:00, H\"UL 186

Soft local phonon modes in thermoelectric materials — •Werner Schweika1 and Raphael Hermann21Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, 52425 Jülich — 2Department of Physics, B5, University of Liege, Belgium

We have studied powders of three different thermoelectric materials, Tl-filled skutterudites[1], Ba- and Sr-filled germanium clathrates[2], and Zn4 Sb3 alloys, by inelastic neutron scattering. For all materials, a common feature of a prominent soft local phonon mode with an energy of about 5 meV has been observed consistently with Einstein modes of rattling atoms in these relatively open cage-like structures. While approaches to thermoelectric properties often focus on the electronic structure our results indicate that local phonon modes play a key role in providing an effective scattering mechanism for the heat transporting acoustic phonons.

[1] Phys. Rev. Lett. 90, 135505-1 (2003).

[2] Phys. Rev. B 72, 174301 (2005).

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2006 > Dresden