Dresden 2011 – wissenschaftliches Programm

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

DS: Fachverband Dünne Schichten

DS 61: Thermoelectric Materials, Thin Films, and Nanostructures III (Focused Session -- Organisers: Nielsch, Rastelli, Balke)

DS 61.6: Vortrag

Freitag, 18. März 2011, 17:15–17:30, GER 37

First principle calculations of nanostructured LAST materials — Jadranka Dokic and •Beate Paulus — Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin

First principle calculations based on different density functionals are performed in order to explain the effects which occur in a solid environment on a microscopical level upon nanostructuring. We are especially interested in, so called LAST-m (AgPb_mSbTe_m+2) crystals which contain a small percentage of silver and antimony atoms incorporated in a lead telluride matrix. The enhancement of thermoelectric efficiency in doped-PbTe is stated to be a consequence of the local increase in the density of states (DOS) over a narrow energy range. Therefore we will analyze the influence of single atom impurities and AgSb pair impurities in various nanostructures within the parent material PbTe. The influence of different doping ratios, relative distances between the impurities, structural relaxations due to doping onto the DOS is determined and discussed. In addition formation energies of the nanostructured solids will be studied and relative stabilities evaluated.