Band-to-band photoluminescence as a probe of electron carriers in Nb-doped SrTiO3 epitaxial thin films

Daisuke Kan, Takuya Shimizu, Yasuhiro Yamada, Ryotaro Aso, Hiroki Kurata, Yoshihiko Kanemitsu, Yuichi Shimakawa

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


In this paper, we describe the use of band-to-band photoluminescence (PL) as a tool for evaluating the quality of Nb-doped STO (Nb: 0.1 at.%) epitaxial thin films. We found that the films with the bulk-equivalent lattice parameters show a large variation in their band-to-band PL properties. In combination with the transport property characterizations, we ascribe the variation to the change in the carrier density owing to the carrier compensation by a small amount of point defects, which cannot be detected in structural characterizations. We also show that the band gap of the film is 10meV smaller than that of the single crystal. Our results imply that even a small amount of defects has strong influences on the physical properties of the Nb-doped STO thin films and that the band-to-band PL is useful for elucidating these influences.

Original languageEnglish
Article number015503
JournalApplied Physics Express
Issue number1
Publication statusPublished - Jan 2014
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Engineering(all)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Band-to-band photoluminescence as a probe of electron carriers in Nb-doped SrTiO<sub>3</sub> epitaxial thin films'. Together they form a unique fingerprint.

Cite this