Impact of Ce concentration on scintillation properties of Lu2xGd2(1-x)SiO5:Ce (LGSO, x=0.2) single crystals

We developed Lu_2xGd_2(1-x)SiO₅ :Ce (LGSO, x=0.2) single crystal as gamma-ray detectors for medical imaging applications. Scintillation properties of LGSO were improved by optimized growth conditions and advanced post-growth annealing. We investigated scintillation properties of LGSO samples with Ce 1.3% and Ce 2.0% prepared by improved conditions and compared them with that obtained before improvement. UV-excitation spectra for emission at 424 and 504 nm showed different tendency between Ce 1.3% and Ce 2.0% in wavelength to be enhanced The X-ray emission intensity around 500 nm was enhanced significantly in the improved LGSO with Ce 2.0% compared to the one with Ce 1.3% and the ones before improvement. No significant difference was found in the decay constants between entire emission and that above 460 nm. It is considered that the one with Ce 2.0% prepared by the improved conditions is the most useful for APD detection due to its good scintillation properties and enhanced emission around 500 nm.