Optical and scintillation properties of Sc2O3, Y2O3 and Lu2O3 transparent ceramics synthesized by SPS method

• Sc2O3, Y2O3 and Lu2O3 transparent ceramics are fabricated by SPS.
• Light yields of Sc2O3, Y2O3 and Lu2O3 are measured under gamma-ray excitation.
• Among them, Sc2O3 showed the highest light yield.
• Decay time profiles of them were evaluated by pulse X-ray streak.

Sc2O3, Y2O3 and Lu2O3 transparent ceramics were prepared by the spark plasma sintering (SPS) method. After polishing, the samples were semitransparent. Their optical transmittance was 10–40% at 500 nm which corresponded with their semi-transparency. In the X-ray induced emission spectra, a broad emission peak appeared around 335 nm in each sample. For this wavelength, scintillation decay time for Y2O3 and Sc2O3 were 22 and 48 ns, respectively. The light yield of Sc2O3, Y2O3 and Lu2O3 was 16,200, 2600, and 200 ph/5.5 MeV-alpha, respectively, which followed from the alpha-ray induced pulse height spectra. The gamma-ray induced light yield of Sc2O3 was 11,500 ph/MeV, which is 1.4 times larger than that of conventional single crystal BGO (Bi4Ge3O12) scintillator. Light yield non-proportionality and energy resolution of Sc2O3 were examined for the first time.