Optical and scintillation properties of Ce-doped LuLiF4 with different Ce concentrations

The crystals of 0.1, 0.5, and 1 mol% Ce-doped LuLiF4 (Ce:LLF) grown by the micro-pulling down (μ-PD) method were examined for their optical and scintillation properties. Ce:LLF crystals had ~80% transparency at wavelengths longer than 300 nm. In photoluminescence spectra, they demonstrated intense emission peaks at 310 and 330 nm with the quantum yield of 60–90%. Ce3+ 5d–4f emission peaks were also detected at similar wavelengths of 310 and 330 nm in the radioluminescence spectra obtained under X-ray excitation. According to pulse height spectra recorded under γ-ray irradiation, the absolute light yield of Ce 0.1, 0.5, and 1% were 3600±400, 3000±300, and 1700±200 ph/MeV, respectively. Decay time kinetics was also inspected using a pulse X-ray equipped streak camera system. The decay time components of Ce:LLF were ∼70 ns and ∼1 μs for all the samples.