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In this study, we propose novel three-layer composite scintillators designed for the simultaneous detection of different ionizing radiation components. These scintillators are based on epitaxial structures of LuAG and YAG garnets, doped with Ce3+ and Sc3+ ions. Samples of these composite scintillators, containing YAG:Ce and LuAG:Ce single crystalline films with different thicknesses and LuAG:Sc single crystal substrates, were grown using the liquid phase epitaxy method from melt solutions based on PbO-B2O3 fluxes. The scintillation properties of the proposed composites, YAG:Ce film/LuAG:Sc film/LuAG:Ce crystal and YAG:Ce film/LuAG:Ce film/LuAG:Sc crystal, were investigated under excitation by radiation with α-particles from a 239Pu source, β-particles from 90Sr sources and γ-rays from a 137Cs source. Considering the properties of the mentioned composite scintillators, special attention was paid to the ability of simultaneous separation of the different components of mixed ionizing radiation containing the mentioned particles and quanta using scintillation decay kinetics. The differences in scintillation decay curves under α- and β-particle and γ-ray excitations were characterized using figure of merit (FOM) values at various scintillation decay intensity levels (1/e, 0.1, 0.05, 0.01). [ABSTRACT FROM AUTHOR]

Single-crystalline films (SCFs) of the LuAG: Ce garnet grown using the liquid-phase epitaxy method onto YAG single-crystal (SC) substrates were investigated for possible applications as composite thermoluminescent (TL) detectors. Such detectors may help to register the different components of ionizing radiation fields with various penetration depths, e.g., heavy charged particles and gamma or beta rays. It was found that the TL signal of LuAG: Ce SCF sufficiently differs from that of the YAG substrate concerning both the temperature and wavelength of emissions. Furthermore, even by analyzing TL glow curves, it was possible to distinguish the difference between weakly and deeply penetrating types of radiation. Within a test involving the exposure of detectors with the mixed alpha/beta radiations, the doses of both components were determined with an accuracy of a few percent. [ABSTRACT FROM AUTHOR]

In this study, the infrared optically stimulated luminescence (IRSL) of single crystals of Ce3+ doped yttrium aluminum garnet (YAG) was investigated for the first time. It was found that infrared stimulation of these crystals, following previous exposure to beta radiation, produces a strong luminescence signal. The highest luminescence efficiency was exhibited by the YAG crystal with 0.1% of Ce. With this crystal, it was possible to measure as low doses as 0.1 mGy. Moreover, IRSL is mainly related to the TL peak at a relatively high temperature of c.a. 175 °C, which leads to quite good stability of the signal in time. These properties create good prospects for potential applications of YAG:Ce in dosimetric radiation measurements [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The development of a novel composite phosphor converter based on single‐crystalline films of Tb3Al5O12:Ce garnet and Y3Al5O12:Ce single‐crystal substrate is reported. The liquid phase epitaxy growth method is chosen for the fabrication of the Tb3Al5O12:Ce/Y3Al5O12:Ce epitaxial structures with excellent photoconversion properties for application in white light‐emitting diodes (LEDs). The influence of Ce3+ concentration and thickness of Y3Al5O12:Ce substrate as well as the thickness of Tb3Al5O12:Ce films on the photoconversion properties is investigated for the construction of warm white LEDs prototypes based on the developed composite phosphor converters. [ABSTRACT FROM AUTHOR]

This paper presents our achievement in the development of new types of advanced composite scintillators (CSs) based on the single crystalline films (SCFs) of Lu3Al5O12 (LuAG) garnet, doped with Pr3+ and Sc3+ ions, and substrate from single crystals (SCs) of Ce3+-doped LuAG using the technology of liquid phase epitaxy. We show the possibility of the simultaneous registration of $\alpha$ -particles and $\gamma$ -quanta by means of separation of the decay kinetics of SCF and crystal parts of such CSs. Namely, the significant differences in the scintillation decay kinetics of LuAG:Pr SCF/LuAG:Ce SC and LuAG:Sc SCF/LuAG:Ce SC CSs under excitation by $\alpha$ -particles of 241Am (5.5 MeV) source and $\gamma$ -quanta of 137Cs (662 keV) source are observed. Thus, such types of CSs can be successfully applied for separation of the signals coming from their film and crystal parts at the registration of the mixed radiation fluxes of $\alpha$ -particles and $\gamma$ -quanta. [ABSTRACT FROM AUTHOR]

The paper is dedicated to development of the novel scintillating screens based on single crystalline films (SCF) of Ce doped Lu3 - x{Tb_x}{Al5 - y}{Ga_y}{O12} multicomponent garnets at x = 2 - 3 and y = 0 - 2.5 onto Y_3Al_5O12 (YAG) and Gd_3Al2.5{Ga2.5}{O12} (GAGG) substrates using the liquid phase epitaxy (LPE) method. We report the optimized content and high scintillation figure of merit of SCF of these garnets grown by the LPE method with using PbO based flux. Namely, the Tb_3Al2.5{Ga2.5}{O12}:Ce SCFs possess the highest values of light yield (LY) compared to all earlier investigated SCF samples, with their LY exceeding by 2.35 and 1.15 times the LY values for YAG:Ce and LuAG:Ce SCF scintillators, respectively. The SCFs of the mentioned compounds show very lower thermoluminescence in the above room temperature range and relatively fast scintillation decay. [ABSTRACT FROM AUTHOR]

The paper is dedicated to development of the novel scintillating screens based on single crystalline films of Ce doped multi-component (Gd,Y,Lu)3(Al,Sc)5O12 garnets onto Gd3Ga5O12 substrates using the liquid phase epitaxy method. [ABSTRACT FROM PUBLISHER]

This work reviews our R&D of new types of scintillating screens based on the single crystalline films (SCF) of Lu,Y orthosilicate, perovskite and garnet compounds grown by the liquid phase epitaxy method. The scintillation and luminescent properties of the following types of SCF scintillators are considered in this work: i) Ce-doped SCF of Y,Lu-based orthosilicates and perovskites with the \ Ce^3+ emission in the 325–600 nm and 360–370 nm ranges with a decay time of 20–33 ns and 16–17 ns, respectively; ii) Ce,Tb doped SCF of Y,Lu-based orthosilicates and perovskites with the simultaneous \ Ce^3+ and \ Tb^3+ emission in the blue or UV and green spectral ranges, respectively; iii) \ Sc^3+ doped SCF of Y-Lu-Al-garnets, emitting in the 290–400 nm range due to formation of the \ ScY,Lu and \ ScAl centers with a decay time of the order of hundreds of nanoseconds. [ABSTRACT FROM PUBLISHER]

This manuscript summarizes recent results on the development of composite luminescent materials based on the single-crystalline films and single crystals of simple and mixed garnet compounds obtained by the liquid-phase epitaxy growth method. Such composite materials can be applied as scintillating and thermoluminescent (TL) detectors for radiation monitoring of mixed ionization fluxes, as well as scintillation screens in the microimaging techniques. The film and crystal parts of composite detectors were fabricated from efficient scintillation/TL materials based on Ce3+-, Pr3+-, and Sc3+-doped Lu3Al5O12 garnets, as well as Ce3+-doped Gd3−xAxAl5−yGayO12 mixed garnets, where A = Lu or Tb; x = 0–1; y = 2–3 with significantly different scintillation decay or positions of the main peaks in their TL glow curves. This work also summarizes the results of optical study of films, crystals, and epitaxial structures of these garnet compounds using absorption, cathodoluminescence, and photoluminescence. The scintillation and TL properties of the developed materials under α- and β-particles and γ-quanta excitations were studied as well. The most efficient variants of the composite scintillation and TL detectors for monitoring of composition of mixed beams of ionizing radiation were selected based on the results of this complex study. [ABSTRACT FROM AUTHOR]

• CS based on the GAGG:Ce SCF and SC with different Ga content were created using LPE. • Differences in the SD kinetics CS under α- and γ-rays excitations were observed. • CS can be successfully applied for simultaneous registration mixed radiation fluxes. This work presents the results of creation of novel composite scintillators based on the Gd 3 Al 5-x Ga x O 12 :Ce (x = 1.16–2.67) single crystalline films (SCF), grown by the LPE method onto Gd 3 Al 2.5 Ga 2.5 O 12 :Ce single crystal (SC) substrates. The scintillation properties of film/crystal epitaxial structures were investigated under α–particle and γ–quantum excitations. Under α–particle excitation, the light yield of mentioned SCF scintillators is significantly less than that in their substrates due to the influence of Pb2+ flux contamination and formation of Pb2+-Ce4+ centers. Meanwhile, these SCF scintillators under α–excitation possess significantly faster decay kinetics than that of their substrates under γ–excitation. Therefore, the Gd 3 Al 5-x Ga x O 12 :Ce SCFs (x = 1.16–2.67) /Gd 3 Al 2.5 Ga 2.5 O 12 :Ce SC epitaxial structures can be used as composite scintillators for simultaneous registration of the components of mixed ionizing fluxes, specifically for detection of α–particles (SCF) and γ–quanta (substrate). The separation of the response from the SCF and substrate parts of composite scintillators under α–particle (241Am) and γ–quantum (137Cs) excitations occurs at large t γ /t α = 1.7–4.2 ratio. [ABSTRACT FROM AUTHOR]

• Instability of the garnet phase and formation of the secondary phase inclusions discussed. • Single crystal growth process and structure of Lu 3 Al 5 O 12 :La studied. • Luminescence and scintillation properties of La Lu and Lu Al defect centers discussed. • Defect related intrinsic luminesce of Lu 3 Al 5 O 12 :La singe crystals investigated. The growth process, crystal composition, optical and scintillation properties of Lu 3 Al 5 O 12 :La (La = 0–0.45%) single crystals were investigated in detail. The thermodynamical stability of the garnet phase formation was studied in the undoped and La doped Lu 3 Al 5 O 12 single crystals. The crystals were grown from the melt using a micro-pulling down method. Detailed composition analysis reviled the complex multiphase character of the samples. Both garnet and α-Al 2 O 3 phases were detected in the undoped and slightly La-doped samples, while heavily La-doped crystals contained the mixture of α-Al 2 O 3 , garnet and perovskites phases. The substitution La for Lu led to the formation of La Lu centers and increased the concentration of Lu Al antisite defects. Both types of centers caused a strong luminescence in the deep UV spectral range. Heavy La-doping significantly enhanced the scintillation performance of Lu 3 Al 5 O 12 crystals. [ABSTRACT FROM AUTHOR]