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Ce:Li 6 Y(BO 3) 3 (LYBO) is a promising thermal neutron scintillator that can be grown into bulk single crystals by the Czochralski method although it melts incongruently. This study achieves 1-inch Ce:LYBO, and demonstrates the collateral flux-growth of LiY 6 O 5 (BO 3) 3 (LYOB) single crystals at the bottom of the crucible during the pulling of LYBO from a stoichiometric melt. Both LYBO and LYOB belong to monoclinic crystal system with the same space group. Thermal analysis shows that LYOB itself is more incongruent than LYBO, decomposing mainly into Y 16.86 B 8 O 38 phase when heated up to 1500 ​°C. In contrast to the typical bluish emission of Ce-doped scintillators, like the case of Ce:LYBO, Ce:LYOB crystals exhibit a broad emission peaking in the orange wavelength region, as a result from an extraordinarily large Stokes shift. The ultrafast photoluminescence (PL) decay of Ce:LYOB is due to dominant non-radiative processes that also cause obvious luminescence quenching. This study reports for the first time high-quality Ce:LYOB single crystals, which are characterized in terms of single crystal diffraction, thermal analysis, optical transmittance, excitation and PL at room temperature, PL decay and Raman spectroscopy. Simultaneous crystal growth of 1-inch Ce:Li 6 Y(BO 3) 3 and millimeter high-quality Ce:LiY 6 O 5 (BO 3) 3 , and investigations on their structure, thermal analysis and optical properties. [Display omitted] • 1-inch Ce:Li 6 Y(BO 3) 3 crystal that is transparent and cracks/inclusion-free. • Flux-growth of high-quality Ce:LiY 6 O 5 (BO 3) 3 single crystals. • Thermal and optical properties of Ce:LiY 6 O 5 (BO 3) 3 were reported for the first time. • Ce:LiY 6 O 5 (BO 3) 3 emits an orange-reddish light originating from large Stokes shift. [ABSTRACT FROM AUTHOR]

The luminescence, scintillation, and photoconversion properties of the single crystals of Ce3+ doped Tb 3−x Gd x Al 5-y Ga y O 12 (х = 0–1.5; у = 2–2.5) mixed garnets, grown by the micro-pulling-down (μ-PD) method, are investigated as a function of the Tb/Gd ratio with the aim of development of phosphor-convertors of white LED and scintillators. The partial Tb3+ substitution by Gd3+ cations leads to the suitable change of the crystal field splitting of the 5d energy levels of Ce3 ions due to different sizes of the Gd3+ and Tb3+ cations. For this reason, the cation engineering enables to improve the luminescence and scintillation characteristics of Tb 3−x Gd x Al 3-2.5 Ga 2-2.5 O 12 crystals due to increasing the efficiency of Gd3+→ Tb3+→ Ce3+ cascade energy transfer observed in these solid solutions. We have shown that from all the crystals under study, the Tb 3-x Gd x Al 2.5 Ga 2.5 O 12 :Ce (х = 1–1.5) crystal is the best promising candidate for the photoconversion and scintillation applications. • Single crystals of TbGdAGG:Ce grown by the micro-pulling-down method. • Tb3+/Gd3+ ratio control improving the color rendering and scintillation properties. • The best photoconversion properties are shown by Tb 2-1.5 Gd 1-1.5 Al 2.5 Ga 2.5 O 12 :Ce. [ABSTRACT FROM AUTHOR]

Single crystal growth of undope CaCl 2 , CaBr 2 and CaI 2 was performed by Bridgman–Stockbarger (BS) method. Investigations of their crystal phases, luminescence and scintillation properties such light yield, energy resolution decay time were performed. In addition, linearity of gamma-ray response in 32–1275 keV range were also evaluated. The light output of 106,000 photon/MeV, energy resolution of 3.2%@662 keV, and scintillation decay time of 834 ns (84%) 1460 ns (16%) were observed. Luminescence properties of CaBr 2 also firstly reported. [ABSTRACT FROM AUTHOR]