Luminescence Properties and Their Temperature Dependence of ${\rm Lu}_{2}{\rm Si}_{2}{\rm O}_{7}:{\rm Ce}$ Scintillation Crystals

Cerium-doped lutetium pyrosilicate (LPS:Ce) crystal with dimension of Φ 10 × 40 mm was grown successfully by Czochralski method. Its crystal structure was determined to be monoclinic with space group of C2/m. The optical transmission, UV and X-ray excited emission spectra, as well as decay curves were measured from 77 K to 500 K. Two emission peaks, 380 nm and 403 nm result from the transition of electrons from 5d₁ to two ground levels (²F_5/2 and ²F_7/2) of Cerium ions (Ce³⁺) in the LPS:Ce crystals. The decay time of the fluorescence is weakly increasing from 77 K to 400 K and then decreases sharply. The light output of LPS:Ce can be improved greatly by annealing at 1400°C in air. TSL peak at 543 K in LPS:Ce is suggested to be related to oxygen vacancies which are one of the reasons of the poor light output.