Shallow electron traps formed by Gd2+ ions adjacent to oxygen vacancies in cerium-doped Gd3Al2Ga3O12 crystals

Mamoru Kitaura, Shinta Watanabe, Kei Kamada, Kyoung Jin Kim, Masao Yoshino, Shunsuke Kurosawa, Toru Yagihashi, Akimasa Ohnishi, Kazuhiko Hara

研究成果: Article査読

8 被引用数 (Scopus)


To clarify the origin of shallow electron traps in cerium-doped Gd3Al2Ga3O12 (Ce:GAGG), the optical properties of cerium-doped Lu3- xGdxAl2Ga3O12 crystals were investigated. Absorption spectra for x = 3 exhibited a prominent band at 12 000 cm-1 when excited by 3.31-eV ultraviolet light. This band has been previously attributed to shallow electron traps at defect complexes associated with oxygen vacancies. When Gd3+ ions were replaced with Lu3+ ions, the 12 000 cm-1 band weakened and disappeared completely for Ce:Lu3Al2Ga3O12. In addition, thermally stimulated luminescence glow curves were observed. Optically stimulated luminescence indicated that the energy of the conduction band minimum did not change by the presence of Lu3+ ions. Thus, the Gd3+ ions were important for the formation of shallow electron traps in Ce:GAGG. First-principles calculations implied that Gd3+ ions responsible for shallow electron traps formed antisite defects at GAGG octahedral sites. Hence, defect complexes of antisite Gd2+ ions adjacent to oxygen vacancies were the most plausible candidates for shallow electron traps in Ce:GAGG.

ジャーナルApplied Physics Letters
出版ステータスPublished - 2018 7 23

ASJC Scopus subject areas

  • 物理学および天文学(その他)


「Shallow electron traps formed by Gd<sup>2+</sup> ions adjacent to oxygen vacancies in cerium-doped Gd<sub>3</sub>Al<sub>2</sub>Ga<sub>3</sub>O<sub>12</sub> crystals」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。