Dresden 2009 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

DF: Fachverband Dielektrische Festkörper

DF 14: Photonic Dielectrics III

DF 14.8: Vortrag

Donnerstag, 26. März 2009, 12:40–13:00, WIL A317

Study of vacancies and extended defects in SrTiO₃
— •M. Zschornak^1,2, E. Gutmann², H. Stöcker², I. Shakhverdova², T. Weißbach², D.C. Meyer², and S. Gemming¹ — ¹Institute of Ion Beam Physics and Materials Research, FZ Dresden-Rossendorf, 01328 Dresden, Germany — ²Institute of Structural Physics, TU-Dresden, 01062 Dresden, Germany

SrTiO₃ is an oxide crystallizing with cubic perovskite-type of structure that exhibits a high tunability of dielectric, electric, mechanical and optical properties by means of defects. Apart from dopants, also intrinsic oxygen vacancies or ordered stacking faults, e.g. Ruddlesden-Popper (RP) phases SrO(SrTiO₃)_n, may influence these properties. We have investigated the structural stability, electronic properties and surface energies of such RP phases up to n=5 by means of density-functional theory. Further, we have theoretically verified an anisotropic reversible elastic softening along an O-deficient ⟨100⟩ direction recently found in nano-indentation of SrTiO₃ under influence of an electric field.