Scintillation properties of transparent Lu3Al5O12 (LuAG) ceramics doped with different concentrations of Pr3+

Transparent ceramics of Pr-doped (0.2 mol%, 0.6 mol%, 1 mol%, and 2 mol%) Lu3Al5O12 (LuAG) scintillators produced by the sintering method are discussed. These materials were cut to the specimens with physical dimensions of 5 x 5 x 2 mm(3). Similar size specimens were also prepared from Czochralski grown Pr:LuAG single crystals to compare scintillation properties. Their transmittance and radio luminescence spectra were evaluated. All specimens were highly transparent in wavelength range above 300 nm, and intense Pr3+ 5d-4f emission was detected around 310 and 370 nm under excitation with X-ray. Under Cs-137 gamma-ray is irradiation, 2 keV photoabsorption peaks were also clearly observed in each sample. The Pr 0.6 mol% doped LuAG ceramics demonstrated highest light yield achievable among the ceramics, and it was half of that observed in the single crystals. Under pulse X-ray excitation, the decay time constants became faster when Pr concentration increased, and. the fastest decay (similar to 5.7 ns time constant) was noticed in the 2 mol% doped ceramic. (c) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim