Switching Ti valence in SrTiO3 by a dc electric field.
A (001) SrTiO3 wafer has been investigated in situ at room temperature under application of a static electric field of varying polarity by fluorescence x-ray absorption near edge structure (XANES) analysis at the Sr-K and Ti-K absorption edges. The XANES spectra show a clear shift of the Ti-K absorption edge energy. The shift is attributed to a change of the Ti valence state in a volume invoked by diffusion of the oxygen ions and vacancies. No shift was observed for the Sr-K absorption edge energy. Theoretical calculations support these findings.
Leisegang
T
T
Institut für Strukturphysik, Technische Universität Dresden, 01062 Dresden, Germany. leisegang@physik.tu-dresden.de
Stöcker
H
H
Levin
A A
AA
Weissbach
T
T
Zschornak
M
M
Gutmann
E
E
Rickers
K
K
Gemming
S
S
Meyer
D C
DC