Resonant X-ray emission at Ti K and Ba L edges in BaTiO

Yoshii, Kenji  ; Yoneda, Yasuhiro   ; Jarrige, I.*; Suzuki, Chikashi ; Ito, Yoshiaki*; Yoshikado, Shinzo*; Fukushima, Sei*

We have observed the electronic structures of ferroelectric BaTiO by means of resonant X-ray emission spectroscopy (RXES) at Ba-L and Ti-K edges. High- resolution X-ray absorption spectra using RXES at Ba-L edge showed no temperature dependence below and above the Curie temperature. This result is different from the previous data, in which the change of spectral shape suggested the displasive mechanism. Thus, a careful reexamination is needed in future. The RXES measurements at Ti-K edge showed the presence of fluorescence peak only, indicating that the excited electron is raplidly delocalied. This suggests the strong covalency between Ti and O and is consistent with the previously proposed mechanism of the ferroelectricity.