DPG Phi
Verhandlungen
Verhandlungen
DPG

Dresden 2006 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

MA: Magnetismus

MA 24: Magnetic Thin Films III

MA 24.3: Talk

Thursday, March 30, 2006, 10:45–11:00, HSZ 03

EXAFS on electron-doped La0.7A0.3CoO3 — •Christian Pinta1,2, Dirk Fuchs1, Eric Pellegrin1, Peter Adelmann1, Stefan Mangold3, and Stefan Schuppler11Forschungszentrum Karlsruhe, Institut für Festkörperphysik, D-76021 Karlsruhe — 2Universität Karlsruhe, Fakultät für Physik,D-76128 Karlsruhe — 3Forschungszentrum Karlsruhe, Institut für Synchotronstrahlung, D-76021 Karlsruhe

Cobaltites are currently receiving intense interest. Especially intriguing is the large number of interactions in this mixed-valent family of compounds (like Hund’s coupling, double exchange, correlation, and crystal field) that occur on similar energy scales and may lead to a number of mutually competing phases. Up until recently it was impossible to dope cobaltites with electrons, and it still is for bulk material. For epitaxial thin-film systems, however, we have performed the first successful synthesis of single-phase electron-doped lanthanum cobaltites, La1−xAxCoO3 (A=Ce or Te). These films exhibit ferromagnetic order with transition temperatures TC of about 85K and 20K for Te and Ce doping, respectively. To better understand the interplay between local structure, doping, and magnetism, we performed Co K-edge EXAFS measurements on three cobaltite thin-film systems: La0.7Ce0.3CoO3, La0.7Te0.3CoO3, and LaCoO3. For further comparison to bulk material, we also carried out measurements on powder samples of undoped LaCoO3. Partial substitution of La by Ce and Te as well as the epitaxial growth clearly affect the local structure; possible implications for the doping-related electronic structure and spin states will be discussed.

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