Dresden 2011 – wissenschaftliches Programm

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

TT: Fachverband Tiefe Temperaturen

TT 10: Poster Session: Superconductivity

TT 10.36: Poster

Montag, 14. März 2011, 14:00–18:00, P4

Temperature dependence of itinerant holes of Bi(Pb)-2212 single crystals in the nearly optimally and under -doped regime by XAS — •Ailakbar Ghafari, Ahmad Kamal Ariffin, Christoph Janowitz, Helmut Dwelk, Rüdiger Mitdank, Alica Krapf, and Recardo Manzke — Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, D-12489 Berlin, Germany

We have measured x-ray absorption spectra at the CuL₃ edge for nearly optimum and slightly under-doped single crystals of Bi(Pb)-2212 in a temperature range of 10 K to 300 K. Both fluorescence and total electron yield modes were used. Analysis of the XAS data obtained on the CuL₃ edge yields the change of hole density in the CuO₂ planes with temperature showing a pronounced minimum between 100 K and 200 K. The results are compared to studies on other HTc samples and existing ideas on its origin. Additional the Hall coefficient was determined experimentally by transport measurements at temperatures between 10 K and 300 K. Tentatively an empirical formula to calculate the temperature dependence of the hole density in form of a linear relation with three terms and a second empirical formula of the temperature dependence of the Hall coefficient is not strictly a derivation.