Identification of ultradilute dopants in ceramics

Isao Tanaka, Teruyasu Mizoguchi, Masafumi Matsui, Satoru Yoshioka, Hirohiko Adachi, Tomoyuki Yamamoto, Toshihiro Okajima, Masanori Umesaki, Wai Yim Ching, Yoshiyuki Inoue, Masataka Mizuno, Hideki Araki, Yasuharu Shirai

Research output: Contribution to journalArticlepeer-review

82 Citations (Scopus)


The properties of ceramic materials are strongly influenced by the presence of ultradilute impurities (dopants). Near-edge X-ray absorption fine structure (NEXAFS) measurements using third-generation synchotron sources can be used to identify ultradilute dopants, provided that a good theoretical tool is available to interpret the spectra. Here, we use NEXAFS analysis and first-principles calculations to study the local environments of Ga dopants at levels of 10 p.p.m in otherwise high-purity MgO. This analysis suggests that the extra charge associated with substitutional Ga on a Mg site is compensated by the formation of a Mg vacancy. This defect model is then confirmed by positron lifetime measurements and planewave pseudopotential calculations. This powerful combination of techniques should provide a general method of identifying the defect states of ultradilute dopants in ceramics.

Original languageEnglish
Pages (from-to)541-545
Number of pages5
JournalNature Materials
Issue number8
Publication statusPublished - Aug 2003
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • General Chemistry
  • General Materials Science
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


Dive into the research topics of 'Identification of ultradilute dopants in ceramics'. Together they form a unique fingerprint.

Cite this