Effect of thermal annealing on scintillation properties of Ce:GdYGaAlO under different atmosphere.

Cerium-doped 1% Ce:GdYGaAlO(GYGAG) single crystal samples grown via Czochralski method were annealed under air, O and N atmospheres from 350 to 1400 °C. The X-ray excited luminescence spectra, energy spectra and UV as well as thermally stimulated luminescence (TSL) spectra were performed comparatively on 'as-grown' and thermally annealed samples. It was found that the luminescence efficiency after annealing in air and O was significantly enhanced compared to the non-annealed samples and this phenomenon was suggested to be caused by the existence of some oxygen vacancies in the Ce:GYGAG crystals. And the oxygen vacancies in the as-grown GYGAG crystals can be effectively eliminated by means of annealing in O containing atmosphere without changing the luminescence mechanism. From the TSL curves before and after annealing, three traps within 77-650 K were found to be related to oxygen vacancies. [ABSTRACT FROM AUTHOR]