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The optical and scintillation properties of Ce3+-doped YGd2(Al,Ga)5O12 single crystal scintillators were investigated. The Ce3+ 5d-4f emission was blue-shifted with increasing Ga content due to the decrease of the crystal field strength. Temperature dependence of the photoluminescence decay times was measured and the thermal activation energy for the luminescence quenching was calculated. Light yield (LY) and its dependence on an integration time were measured under γ-ray excitation. The fast component content in the scintillation response increases with increasing Ga content. The YGd2Al2Ga3O12:Ce sample showed a high LY of 38,000 photons/MeV. The decrease of LY value observed for a YGd2Al1Ga4O12:Ce sample is mainly due to the thermal ionization of the 5d1 excited state of the Ce3+ emission center to the conduction band.

This report presents the luminescence and scintillation response of Ce3+-doped oxide glasses with high Gd2O3 (30 mol%) content. The characteristic emission of Ce3+ 5d → 4f transition peaking around 380 nm was observed in its luminescence spectra under UV and X-ray excitation. Photoluminescence decay kinetics was governed by a few tens of nanoseconds decay time. The integral scintillation efficiency of about 22% of that of the Bi4Ge3O12 scintillator was obtained under X-ray irradiation. The light yield and its dependence on the integration time were measured and compared with that of the Bi4Ge3O12 crystal. The total mass attenuation coefficient at 662 keV γ-rays was also determined and compared with the theoretical one calculated using the WinXCom program.

Dy3+‐doped oxide glass with 30 mol.% Gd2O3content in the glass host was prepared by melt quenching under CO reducing atmosphere. The luminescence properties were investigated under UV and X‐ray excitation. The 4F9/2→6HJ(J= 15/2, 13/2, 11/2, and 9/2) luminescence was observed with intense blue (484 nm; 4F9/2→6H15/2) and yellow (576 nm; 4F9/2→6H13/2) emissions. Energy transfer from Gd3+to Dy3+ions was confirmed by photoluminescence excitation and emission spectra as well as photoluminescence decay measurements. The integral scintillation efficiency of 11% of Bi4Ge3O12scintillator was obtained.

The glass‐ceramics (GC) of gadolinium aluminum gallium garnets with the expected composition of Gd3Al3Ga2O12:Ce and Gd3Al3Ga2O12:Ce,Be (GAGG:Ce and GAGG:Ce,Be, respectively) are fabricated by crystallization from the Gd2O3–Al2O3–Ga2O3–CeO2–SiO2–BeO (Gd:Ga:Al ratio is close to 3:2:3) glasses. The influence of Be2+co‐doping (including doping level) on the luminescent properties of the GAGG is demonstrated. In particular, Be co‐doping results in the suppression of the Ce3+‐related radioluminescence (RL) and as a consequence, the light yield is lowered as well. The conclusion is made that Be2+creates effective electron or hole trapping centers. The article is about the glass‐ceramics form of Gd3Al3Ga2O12:Ce and Gd3Al3Ga2O12:Ce,Be, gadolinium aluminum gallium garnets. Be2+co‐doping affects the luminescent properties of Ce3+in these materials by the suppression of light yield. Moreover, the decay time of the photoluminescence (PL) decreases upon beryllium content. These observations lead to the conclusion of the effective beryllium‐based charge trapping centers’ existence.

Vacuum ultraviolet (VUV) excitation spectra at 10 K have been recorded for the lanthanide ions, Ln3+= Nd3+, Ho3+, Tm3+, and Yb3+, situated at octahedral site symmetry in hexafluoroelpasolite Cs2NaLnF6lattices. The corresponding VUV/UV/visible/near-infrared emission spectra have also been recorded. The 4fN−15d energy levels and 4fN−4fN-15d spectral intensities have been calculated by judicious selection of parameters, without detailed fittings, when employing the M. F. Reid suite of programs. The simulations are in reasonable agreement with experimental data. Some additional spectral features for these systems have been assigned to charge transfer (CT) transitions, and CT emission is reported for the case of Tm3+. A comparison of the results with the spectra of LiYF4:Ln3+has been included and the major difference lies in the greater crystal-field strengths for Ln3+in the hexafluoroelpasolite lattices.

We report a breakthrough concept for a bulk single crystal as a heavy aluminum perovskite scintillator, where due to bandgap engineering by a balanced Gd admixture in a Lu cation sublattice, the scintillation performance dramatically increases. In an optimized composition of (Lu, Gd)AlO3:Ce (LuGdAP:Ce), the light yield approaches 21,000 phot/MeV, which is close to that of classical but much less dense YAP:Ce and 50% higher than the best LuYAP:Ce reported in the literature. Moreover, contrary to LuYAP:Ce, the LuGdAP host maintains a high effective atomic number close to that of LuAP:Ce (Zeff= 64.9), which is comparable to commercial LSO:Ce. An enormous decrease in afterglow on the millisecond time scale and acceleration in the rise time of the scintillation response further increase the application potential of the LuGdAP host. The related acceleration of the transfer stage in the scintillation mechanism due to diminishing electron trap depths is proven by thermally stimulated luminescence (TSL). Furthermore, we quantitatively characterize and model the energy transfer processes that are responsible for the change in the photoluminescence and scintillation decay kinetics of Ce3+in the LuGdAP matrix. Such an innovative (Lu, Gd)AP:Ce scintillator will become competitive for use in applications that require heavy, fast, and high light yield bulk scintillators.

Ce3+,Pr3+‐codoped SiO2–Al2O3–B2O3–Gd2O3glasses (SABG:Ce,Pr) were prepared by melt quenching under a CO reducing atmosphere. Luminescence properties were investigated under UV and X‐ray excitations. A dominant emission band at 430 nm belonging to the Ce3+:5d1→ 4f transition was observed in the photo‐ and radio‐luminescence spectra. The energy transfer occurs from this Ce3+band toward the 3PJlevels of Pr3+with an efficiency of up to 24%, followed by the reduction of integrated luminescence intensity with an increasing Pr3+concentration. This result is attributed to the increase in the reabsorption of Ce3+luminescence and the non‐radiative energy transfer toward the 3PJlevels of Pr3+. The cross‐relaxation process within the Pr3+pairs can further diminish the total luminescence yield at high Pr3+concentrations. The integral scintillation efficiency and light yield measurements were carried out and compared to the reference Bi4Ge3O12(BGO) crystal.