We demonstrate the potential of magnesium (Mg2+) co-doping in Ce3+-doped gadolinium aluminum gallium garnet Gd-3(Ga3Al2)O-12 (GAGG:Ce) scintillating crystals to obtain a fast decay time performance and the feasibility of mu-PD technique for growing GAGG:Ce,Mg with high dopant concentrations. We demonstrate that Mg2+ co-doping can enhance scintillation kinetics through compositional engineering. An ultra-fast effective decay time of similar to 1 ns was achieved with 2500 ppm Ce and 500 ppm Mg, suggesting that Mg2+ co-doping modulates energy transfer pathways through Ce3+/Ce4+ activator ions effectively. These results pave the way for the development of ultrafast scintillator materials.

Aliovalent codoping is an effective strategy for improving the performance of Ce-doped scintillators. We grew Ce-doped yttrium aluminum garnet (YAG:Ce) single crystals codoped by two divalent ions, Mg2+ and Ca2+, in various ratios. Using time-resolved photo-, cathodo-, and radioluminescence spectroscopy, transient optical absorption, light yield, and coincidence time resolution measurements, we investigated the specificity of the influences of these two aliovalent codopants on the properties of YAG:Ce scintillator. Mg codoping diminishes the influence of electron capture at shallow traps and accelerates the luminescence response at minor conversion of Ce3+ to Ce4+. Meanwhile, Ca codoping results in a substantial acceleration of scintillation due to the valency transformation, the suppression of electron-trap influence via channeling electrons to nonradiative recombination centers, and the formation of modified Ce3+ emission centers with a thermal quenching barrier of 0.36 eV, in addition to the regular emission centers with the barrier of 0.8 eV. In heavily Ca-codoped samples, an ultrafast luminescence decay was observed after photoexcitation and excitation with high-energy electrons and 511 keV photons. Because the response rise and decay times decrease more rapidly than the light yield, increasing the Ca content improves the coincidence time resolution to  ∼ 110 ps at a light yield of  ∼ 18 500 ph/MeV.

This study explores co-doping strategies involving Sc 3+ , Ca 2+ , and Mg 2+ in YAG:Ce scintillator, aiming to optimize the balance between scintillation decay time and light yield to meet the demands of next-generation high-energy physics detectors.

This work focuses on the development of fast-timing inorganic scintillators for use in cutting-edge particle physics experiments at colliders and time-of-flight positron emission tomography (TOF-PET). Significant progress in enhancing the timing performance of Y3Al5O12 (YAG) scintillators is reported, achieved by optimizing the codoping conditions with Ca2+ and Mg2+. The optimized crystals exhibit fast rise and decay times of 30 ps and 26 ns, respectively, alongside with an impressive coincidence time resolution (CTR) of 131 ps, while maintaining a high light output of over 22,000 pH/MeV. The incorporation of dopants into the YAG lattice is explored, providing insights into the mechanisms driving scintillation response in YAG:Ce,Ca,Mg crystals. Furthermore, uniformity in scintillation properties was demonstrated along a large, 120 mm-long YAG:Ce,Ca,Mg ingot, which was grown using the Czochralski method in a tungsten crucible.

The influence of gallium content in Y3(Al1-xGax)5O12:Ce on the luminescence properties of this scintillator was studied in a set of Czochralski-grown single crystals with Ga content x varied in the range from 0 to 1. Time-resolved photoluminescence (PL) and cathodoluminescence (CL) spectroscopies were exploited, and temperature dependences of PL properties were studied. A sublinear increase of CL intensity as the excitation intensity increases was observed. The activation energies for thermal quenching in Y3(Al1-xGax)5O12:Ce with Ga content x up to 0.6 were estimated. An increase in the light yield observed with increasing x up to similar to 0.6, despite the decreasing activation energy for thermal quenching, at the resonant excitation to the emitting 5d1 level of Ce3+ is interpreted by an additional mechanism enhancing the Ce3+ emission. The ratio between the luminescence decay time and the light yield, which is a figure of merit for fast timing properties, is improved with increasing Ga content up to similar to 0.5.

This work deals with the optimization of bismuth silicate, Bi4Si3O12 (BSO) scintillation crystals as candidates for future high energy physics experiments at colliders involving the registration of both scintillation and Cherenkov light. Crystals with a high transparency in UV-band and a high timing resolution are required for this application. Czochralski process was employed for BSO crystal growth in Pt crucibles in a dynamic growth atmosphere. After the growth of a series of crystals in air, as well as mixed Ar-air static and dynamic atmospheres, it was shown that the mixed atmosphere minimizes Bi2O3 evaporation and reduces the amount of Pt dissolved in the melt by several times. This caused the reduction in the number of foreign inclusions in the grown crystals, providing a transparency of over 70 % in the > 300 nm range, a light output of up to 2140 ph/MeV, an energy resolution of 21.5 % at 662 keV gamma-rays, while a coincidence time resolution was improved from 148 to 125 ps.

The influence of gallium content in Y3(Al1−xGax)5O12:Ce on the luminescence properties of this scintillator was studied in a set of Czochralski-grown single crystals with Ga content x varied in the range from 0 to 1. Time-resolved photoluminescence (PL) and cathodoluminescence (CL) spectroscopies were exploited, and temperature dependences of PL properties were studied. A sublinear increase of CL intensity as the excitation intensity increases was observed. The activation energies for thermal quenching in Y3(Al1−xGax)5O12:Ce with Ga content x up to 0.6 were estimated. An increase in the light yield observed with increasing x up to ∼0.6, despite the decreasing activation energy for thermal quenching, at the resonant excitation to the emitting 5d1 level of Ce3+ is interpreted by an additional mechanism enhancing the Ce3+ emission. The ratio between the luminescence decay time and the light yield, which is a figure of merit for fast timing properties, is improved with increasing Ga content up to ∼0.5.

The work deals with timing characteristics of garnet scintillation materials, especially for applications like time-of-flight PET or future collider experiments. While cerium-activated oxide scintillation single crystals are known for their fast performance due to rapid d-f relaxation in Ce 3+ . Meanwhile, the extended scintillation decay time of Gd 3 (Al,Ga) 5 O 12 :Ce (GAGG:Ce), the brightest oxide scintillator, still does not meet the requirements for the upgrade 2 of the central part of the LHCb electromagnetic calorimeter in CERN. Additionally, GAGG:Ce and other Ga-containing scintillators are typically grown in large sizes exclusively in Ir crucibles. Attempts to substitute Ga with Sc in the gadolinium garnet Gd 3 (Al,Sc) 5 O 12 :Ce (GSAG:Sc,Ce) grown from Mo crucibles resulted in a significant decrease in light yield compared to GAGG:Ce, although without a notable improvement in timing.The results obtained in this work certify that tuning the doping concentrations of Ca2+ and Mg2+ ions provides the enhancement of timing performance of Ce-doped YAG and GAGG scintillators due to elimination of carrier traps and acceleration of carrier transport to luminescence centers, independently on the host composition. Apart of that, YAG is more promising as host, because it can be obtained in cheap W/Mo crucibles in contrast to GAGG and other Ga-containing crystals. Due to the synergy between Ca2+ and Mg2+ dopants in garnets hosts, we demonstrated that improved combination of light yield and decay time can be achieved in Ce-doped garnets, i.e. larger number of prompt photons can be generated for fast-timing applications. At the same time, Sc,Ca codoped YAG:Ce is another promising approach to get fast scintillation crystals with a high light yield that may be grown by a cheap technology from W crucibles.

The application of a pulsed laser ablation technique for the generation of cerium-doped garnet nanoparticles in liquids is investigated. The morphological and optical properties of the obtained nanoparticles are demonstrated. Features introduced by the single crystals of Gd3Al2.4Ga2.6O12:Ce3+, Lu3Al5O12:Ce3+, and Y3Al1.25Ga3.75O12:Ce3+ from which the nanoparticles are generated, as well as the parameters of a liquid media on the garnet nanoparticle generation are experimentally studied using TEM and UV-Vis spectroscopy methods. It is shown how the size, shape, and internal structure of the nanoparticles are related to the external laser ablation conditions, as well as to the laser melting processes of NPs in the colloidal solutions. This work provides important information about the generated nanoparticles, which can be used as building blocks for specially designed structures with predetermined optical properties.

For the first time to the best of our knowledge, CeAlO 3 nanocrystals with perovskite structure are synthesized by pulsed laser ablation technique. The morphological and optical properties of the obtained CeAlO 3 nanocrystals are investigated. This work opens new prospects for the application of laser ablation methods for the generation of perovskite nanocrystals and development of novel nanocomposite structures, which can be applied for the fabrication of perovskite solar cells, scintillation detectors, catalysts, etc.

Growth technologies of oxide crystals in W/Mo crucibles have been developed as a low-cost alternative to conventional processes involving Ir crucibles. Carbon-containing atmosphere needed to protect crucibles from oxidation leads to the introduction of carbon into the crystal lattice and creation of carbon-related defects, which affect the scintillation performance. Meanwhile, a search for fast scintillators for the new generation of positron-emission tomographs and high-energy physics experiments at colliders is under way. Codoping with divalent cations has become an efficient way to suppress long components of scintillation decay in Ce-doped scintillators. This work addresses Y 3 Al 5 O 12 (YAG) crystals codoped with carbon, cerium activator, and divalent cations. Optical and scintillation properties of YAG:Ce,C, $\text{A}^{2+}$ crystals (A = Ca $^{2+}$ , Mg $^{2+}$ , Ba $^{2+}$ , Sr $^{2+}$ ) are systematically studied. Among all the studied garnet compounds, YAG:Ce,C,Ca $^{2+}$ crystals demonstrated the fastest scintillation decay times, which are promising for the mentioned applications. Mechanisms of scintillation process in the studied materials are discussed. The Ce $^{3+}$ /Ca $^{2+}$ ratio in YAG:Ce,C,Ca $^{2+}$ was optimized to minimize slow components in scintillation decay.

Sesquioxides of lanthanides, yttrium, and scandium are promising hosts for laser and scintillation materials; however, the crystallization of such compounds is complicated by very high melting temperatures, as well as polymorph transitions. This work reports for the first time the growth of Y2O3 and Y2−xScxO3 crystals by the Vertical Gradient Freezing method from tungsten crucibles, proposing an alternative to extremely expensive rhenium and iridium crucibles. Translucent Y2O3 samples are obtained, and their luminescent and scintillation parameters are evaluated. The main issues of Y2O3 crystallization under the proposed conditions are discussed, as well as ways of enhancing the crystal quality. Finally, polymorph transitions are avoided by decreasing the average radius of the rare earth cation by Y3+/Sc3+ substitution, providing transparent Y2−xScxO3 crystals with a cubic structure.

Inorganic scintillators are widely used for scientific, industrial and medical applications. The development of 3D printing with inorganic scintillators would allow the fast creation of detector prototypes for the registration of ionizing radiation, such as alpha, beta and gamma particles in thin layers of active material, and X-ray radiation. This article reports on the technical work and scientific achievements that aimed at developing a new inorganic scintillation filament to be used for the 3D printing of composite scintillator materials: study and definition of the scintillator composition; development of the methods for the inorganic scintillator filament production and further implementation in the available 3D printing technologies; study of the impact of the different 3D printing modes on the material scintillation characteristics. Also, 3D-printed scintillators can be used to produce combined detectors for high-energy physics.

Inorganic scintillators are widely used for scientific, industrial and medical applications. The development of 3D printing with inorganic scintillators would allow fast creation of detector prototypes for registration of ionizing radiation, such as alpha and beta, gamma particles in thin layers of active material and soft X-ray radiation. This article reports on the technical work and scientific achievements that aimed at developing a new inorganic scintillation filament to be used for the 3D printing of composite scintillator materials: study and definition of the scintillator composition; development of the methods for the inorganic scintillator filament production and further implementation in the available 3D printing technologies; study of impact of the different 3D printing modes on the material scintillation characteristics. Also, 3D printed scintillators can be used for creation of combined detectors for high-energy physics.

The paper addresses the development of composite scintillation materials providing simultaneous real-time monitoring of different types of ionizing radiation (α-, β-particles, γ-rays) in mixed fluxes of particles and quanta. The detectors are based on composite heavy oxide scintillators consisting of a thin single-crystalline film and a bulk single-crystal substrate. The film and substrate respond to certain types of ionizing particles, forming together an all-in-one composite scintillator capable of distinguishing the type of radiation through the different time characteristics of the scintillation response. Here, we report the structure, composition, and scintillation properties under different ionizing radiations of (Lu,Gd,Tb)3(Al,Ga)5O12:Ce films deposited using liquid phase epitaxy onto Gd3(Al1−xGax)5O12:Ce (GAGG:Ce) single-crystal substrates. The most promising compositions with the highest light yields and the largest differences in scintillation decay timing under irradiation with α-, β-particles, and γ-rays were selected. Such detectors are promising for environmental security purposes, medical tomography, and other radiation detection applications.

The photo- and radioluminescent properties of the CsPbBr3 nanocrystals in PMMA film on BGO and LGSO: Pr scintillators are studied. Significant photoluminescence decay has been shown. The sensitivity of the CsPbBr3 nanocrystals to X-ray and alpha-particle excitation has been demonstrated despite their low loading in PMMA film.

Langatate (LGT) crystals of La3Ga5.5Ta0 center dot 5O14 composition of diameter 50 mm were grown from the melt by Czochralski technique. Using (1-2 wt %) Ga2O3 excess in the starting charge and growing crystal in mixture argon (0.1-1%O-2) gas atmosphere are a good condition to crystallize LGT under stationary stable regime. The LGT crystals grown along Z-axis exhibit strong faceting. The grown crystals were exempt of inclusions, cracks and secondary phases. The presence of oxygen in the growth chamber is necessary to limit gallium oxide evaporation and strongly affect the crystals coloration and the transmission spectra in the range (200-500 nm). The electrical resistivity is sensitive to the oxygen content in the growth environment.

Bismuth germanate (BGO) is a well known high density scintillating material widely used in many applications such as high energy physics and medical imaging. Bismuth silicate (BSO) features properties similar to BGO in terms of stopping power and Cherenkov photon yield with a lower scintillation light output but faster decay time, thus being more attractive for applications in high-rate environments. Mixed crystals such as Bi-4(GexSi1-x)(3)O-12 (BGSO, with x varying from 0 to 1) make it possible to optimize decay time and light yield based on the detector needs. A characterization campaign of the optical and scintillation properties of two sets of BGSO mixed crystals with Ge fraction varying from 0 to 100% was performed. A coincidence time resolution (CTR) at 511 keV of 208 +/- 2 ps FWHM was measured for a 2 x 2 x 3 mm(3) pixel with 40% Ge, while the optimum value obtained for the effective decay time is 49.9 +/- 1.8 ns for a 6 x 6 x 0.7 mm(3) plate-shaped sample with 30% Ge. Furthermore the smallest slow decay time component achieved is 101 +/- 2 ns and is obtained for the plate-shaped sample with 30% Ge, while the largest is 236 +/- 5 ns for a pure BGO sample with the same geometry. In addition we demonstrated the possibility to efficiently separate the Cherenkov and scintillation light produced in a pure BSO sample. Such a technique could be exploited in a crystal-based dual-readout calorimeter to improve the energy resolution for hadronic showers and jets.

This paper addresses the carbon co-doping of Ce-doped garnets, an efficient scintillation material and white light phosphor. The composition and the optical and scintillation properties of carbon-co-doped Y3Al5O12 (YAG) are studied at different cerium and carbon concentrations. YAG:Ce,C crystals were grown in the Ar + CO atmosphere from W crucibles. The carbon concentration reaches 0.5 atom %, but it does not affect the Ce distribution coefficient. The appearance and elimination of color centers are discussed in comparison to Ce-free YAG:C crystals. The tuning of cerium and carbon concentrations provides a light yield enhancement of up to 29 600 phot/MeV. The achieved enhancement may extend the application range of garnet-type phosphors and scintillators.