Visualizing hidden electron trap levels in Gd3Al2Ga3O12:Ce crystals using a mid-infrared free-electron laser

Mamoru Kitaura, Heishun Zen, Kei Kamada, Shunsuke Kurosawa, Shinta Watanabe, Akimasa Ohnishi, Kazuhiko Hara

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


The energy levels of electron traps (namely, defect complexes associated with oxygen vacancies) in Gd3Al2Ga3O12:Ce (GAGG:Ce) were studied at 12 K using mid-infrared (MIR) light pulses from a free-electron laser (FEL) as the probe light. Ce3+ 5d-4f luminescence was stimulated by the MIR light pulse following an ultraviolet light pulse. Stimulation of Ce3+ 5d-4f luminescence by MIR light pulses was pronounced above 0.31 eV. This result is consistent with that of previous work based on a trap-mediated luminescence model. It is concluded that the electron trap levels are located 0.31 eV below the bottom of the conduction band. This study demonstrates that MIR-FEL is applicable for the determination of hidden electron trap levels.

Original languageEnglish
Article number031112
JournalApplied Physics Letters
Issue number3
Publication statusPublished - 2018 Jan 15

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Fingerprint Dive into the research topics of 'Visualizing hidden electron trap levels in Gd<sub>3</sub>Al<sub>2</sub>Ga<sub>3</sub>O<sub>12</sub>:Ce crystals using a mid-infrared free-electron laser'. Together they form a unique fingerprint.

Cite this