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Pr-doped (Lu1−x, Yx)2Si2O7(x= 0.25, 0.5, and 0.75) crystals were synthesized by the floating zone method. Emission peaks due to 5d–4f transitions of Pr3+were observed at 300 nm under excitation of both UV light and X-rays. Scintillation decay times of 19–22 ns were obtained, and they originated from the 5d–4f transitions of Pr3+. Afterglow levels became high from 64.7 to 541 ppm as the Y-admixed concentration increased. The light yields were estimated to be 560–700 photons MeV−1by comparing the channels of photoabsorption peaks from the pulse height spectra of 137Cs γ-rays measured using prepared crystals and commercial Gd2SiO5reference.

We have studied scintillation properties of Eu3+-doped Gd3Al2Ga3O12single crystals. Gd3Al2Ga3O12single crystals with different concentrations of Eu3+(0.5%, 1.0%, 5.0%, 10.0%, and 15.0%) were grown using the floating-zone method. In photoluminescence (PL) and scintillation properties, the Eu-doped Gd3Al2Ga3O12single crystals showed emission peaks and several millisecond decay times due to 4f–4f transitions of Eu3+ions. Pulse height spectra of all the samples were investigated under γ-ray irradiation from 137Cs (662 keV). The 0.5%, 1.0%, 5.0%, and 10.0% Eu-doped samples showed full energy peaks. Among all the samples, the 5.0% Eu-doped Gd3Al2Ga3O12single crystal showed the highest light yield of 36 000 photons MeV−1.

A lanthanum pyrosilicate (La2Si2O7, LaPS) single crystal is successfully grown with a Ce-doped concentration of 0.5 to 20.0% as well as undoped LaPS for reference. The photoluminescence emission map of Ce-doped LaPS has broad emission at 360–410 nm from Ce3+5d-4f transition, with a decay time of 20–24 ns. In the scintillation properties, Ce-doped LaPS presents the scintillation peak at 390 nm under X-ray excitation, with the decay time constant at 26–31 ns plus another decay constant caused by the emission from host material at 250–600 ns. The afterglow level at 20 ms after X-ray irradiation is around 30–56 ppm. In the 662 keV ?-ray pulse height spectra, 1.0% Ce-doped LaPS shows a clear photoabsorption peak, with a scintillation light yield of 5400 ph MeV-1. The relationship between ?-ray energy and the photoabsorption peak channel (linearity) is also covered in this study.

CaSiO3crystals doped with 0.5%, 1.0% and 2.0% Ce were developed using the floating zone method, and the scintillation and thermally-stimulated luminescence (TSL) properties were evaluated. Under X-ray irradiation, the emission peaks due to the 5d–4f transitions of Ce3+appeared at 360 nm in all the samples. Under 241Am 5.5 MeV α-ray irradiation, a clear full-energy peak appeared in all the samples, and the light yield of the 2.0% Ce doped-sample was 1040 ph/5.5 MeV-α. As a TSL dosimeter, the samples were very sensitive to X-rays and showed a good linear response from 0.1 to 1000 mGy, which was equivalent to the measurable sensitivity of commercial dosimeters for personal dose monitoring.