In-gap state generated by La-on-Sr substitutional defects within the bulk of SrTiO

Local distortion in the conduction pathway has a significant influence on the conducting properties of oxides. The electronic states induced in the band gap of SrTiO 3 by La doping were investigated using photoemission spectroscopy (PES) and soft X-ray emission spectroscopy (SXES); moreover, the loc...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Physical chemistry chemical physics : PCCP 2019-07, Vol.21 (27), p.14646-14653
Hauptverfasser: Aiura, Yoshihiro, Ozawa, Kenichi, Tezuka, Yasuhisa, Minohara, Makoto, Samizo, Akane, Bando, Kyoko, Kumigashira, Hiroshi, Mase, Kazuhiko
Format: Artikel
Sprache:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Local distortion in the conduction pathway has a significant influence on the conducting properties of oxides. The electronic states induced in the band gap of SrTiO 3 by La doping were investigated using photoemission spectroscopy (PES) and soft X-ray emission spectroscopy (SXES); moreover, the local distortion in the conduction pathway was examined using extended X-ray absorption fine structure (EXAFS). An itinerant state and a localized state were observed as a metallic state and an in-gap state, respectively, in the PES spectra and as inelastic peaks in the SXES spectra. This implied that the itinerant state and the in-gap state coexisted within the bulk. From EXAFS results, it was observed that La doped into SrTiO 3 substituted Sr and locally distorted the conduction pathway. The results showed that some electrons doped by La-on-Sr substitution are trapped/localized by the local distortion in the conduction pathway, whereas the remaining doped electrons itinerate in the pristine conduction pathway with no distortion. La-on-Sr substitution defects in SrTiO 3 generate electrons and simultaneously cause local distortion in the conduction pathway.
ISSN:1463-9076
1463-9084
DOI:10.1039/c9cp02307k