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Author

Z. Moroz

Bio: Z. Moroz is an academic researcher. The author has contributed to research in topics: Irradiation & Luminescence. The author has an hindex of 5, co-authored 12 publications receiving 72 citations.

Papers
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Journal ArticleDOI
TL;DR: Yttrium-aluminum garnets, strontium and barium lanthanum gallates, lithium niobate and tantalate as-grown crystals and doped by diffusion with rare-earth (Nd, Dy, Er, Tm, Ho, Pr, Ce) and metal transition elements (Mn, Cr) were investigated optically and using Electron Spin Resonance method before and after gamma, electron and proton irradiation as discussed by the authors.
Abstract: Yttrium-aluminum garnets, strontium and barium lanthanum gallates, lithium niobate and tantalate as-grown crystals and doped by diffusion with rare-earth (Nd, Dy, Er, Tm, Ho, Pr, Ce) and metal transition elements (Mn, Cr) were investigated optically and using Electron Spin Resonance method before and after gamma, electron and proton irradiation.

23 citations

Journal ArticleDOI
TL;DR: In this article, the emission characteristics of a free-running laser, doped with active Ho 3 ions were measured, and the mechanisms which cause changes of the laser properties were discussed.

14 citations

Proceedings ArticleDOI
24 Mar 1999
TL;DR: In this paper, the ESR and ESA spectra of YAG:Ce crystals codoped with Mg2+ ions and subjected to various treatments have been measured and the variations induced by irradiations in gamma and proton beams, and by thermal annealings under oxidation and reduction conditions point to large variations of the cerium ion valency.
Abstract: Absorption, luminescence, ESR and ESA spectra and TL glow curves of YAG:Ce crystals codoped with Mg2+ ions and subjected to various treatments have been measured. The variations induced by irradiations in gamma and proton beams, and by thermal annealings under oxidation and reduction conditions point to large variations of the cerium ion valency. The ESA spectra of Mg-free and Mg-codoped crystals are clearly different with the peak value in the YAG:Ce, Mg sample higher and shifted towards the shorter wavelengths. Although the TL glow curves reveal the existence of the same major traps in both materials, their role in the overall deexcitation process is strongly modified upon Mg-codoping.

9 citations

Journal ArticleDOI
TL;DR: In this paper, the influence of the irradiation by various types of ionizing par-ticles on the efficiency of solid state lasers is investigated. But the effect of the ionizing radiation on the laser performance is not investigated.
Abstract: Studies on the influence of the irradiation by various types of ionizing par-ticleson the efficiency of solid state lasers are motivated by a need of using them in manyapplications, e.g. as range finders, altimeters and others, in intense ex-ternalradiation fields [1]. On the other hand, a positive influence of the ionizing radiation onthe laser performance is also known. In particular such phenomenon was observed inlasers based on Cr, Tm, Ho: Y

7 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of ionization and Frenkel defects on the luminescence changes of YAlO 3 :Er crystal under proton irradiation was investigated. And the accuracy of the intensity measurement of the 0.208 MeV gamma line from 167 Tm to 0.14%, including the statistical and systematic errors, was shown.

5 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, the effect of codopants on the crystal field and defect structure of Gd3Ga3Al2O12 was investigated in detail, including absorption, photoluminescence excitation and emission.
Abstract: Single crystals of Gd3Ga3Al2O12 : Ce with different codopants were successfully grown using the Czochralski technique. Optical and scintillation properties of these codoped crystals were studied in detail including absorption, photoluminescence excitation and emission, decay time and thermoluminescence. This study revealed that while boron codoping improves the scintillation light output and energy resolution and decreases self-absorption in these crystals, calcium codoping affects their properties in the opposite manner. In addition to antisite defects, the effect of room temperature trap centres on the sensitivity of these crystals to light exposure is also reported for the first time. Light sensitivity was also found to be affected with the incorporation of codopants in the lattice. The effect of annealing in oxidizing and reducing atmospheres on the scintillation and optical properties of differently codoped crystals was also investigated in detail in order to better understand the defect structure of these crystals. All these measurements together are used to explain the effect of codoping on the crystal field and defect structure of these crystals.

119 citations

Journal ArticleDOI
TL;DR: In this article, the intrinsic defect structure of RE 3 Al 5 O 12 garnets (where RE ranges from Lu to Gd and Y) is predicted to be the lowest energy intrinsic defect.
Abstract: In order to enhance capabilities for the reliable detection of nuclear material, improved detector materials are required. There is considerable room for improvement within the scintillator family of materials. However, native defects are present in all materials and impurities are similarly common. In scintillators, these defects serve as trap sites for electrons or holes, and therefore may contribute to decreased and delayed light yield. In fact, Lempicki and Bartram [J. Lumin. 81 (1999) 13] have proposed that understanding defect related phenomena is vital to the improvement of scintillators. It follows that if the most egregious electron/hole trapping defects are removed from the system, light output should increase. However, defect removal is difficult to achieve since often the defect-type to be removed is not known. In this paper, we assist the optimization of scintillators by employing atomic scale simulation techniques to predict the intrinsic defect structure of RE 3 Al 5 O 12 garnets (where RE ranges from Lu to Gd and Y). Specifically, we predict cation antisite defects to be the lowest energy intrinsic defect. Furthermore, we describe how our results can be used to interpret experimental observations.

85 citations

Journal ArticleDOI
TL;DR: In this paper, the average grain sizes of Tb 3+ :Y 3 Al 5 O 12 powders have been determined by X-ray powder diffraction measurements and the concentration dependence of the luminescence spectra and lifetimes have been investigated as a function of the YAG grains sizes.

70 citations

Journal ArticleDOI
TL;DR: In this article, the phase purity, composition and microstructural features in the polycrystalline samples were studied by XRD analysis, IR spectroscopy and scanning electron microscopy.

63 citations

Journal ArticleDOI
TL;DR: In this paper, the feasibility of the use of titanium dioxide (TiO2), zinc oxide (ZnO), copper oxide (CuO) and Cadmium oxide (CdO) in the development of thick film gamma radiation sensors with instantaneous dosage readouts was investigated.
Abstract: The aim of this work is to investigate the feasibility of the use of titanium dioxide (TiO2), zinc oxide (ZnO), copper oxide (CuO) and Cadmium oxide (CdO) in the development of thick film gamma radiation sensors with instantaneous dosage readouts. A number of pn-heterojunctions with various compositions of sensitive layers were formed by screen printing the thick film pastes on silicon wafers. All these devices were exposed to a disc-type 137Cs source with an activity of 370 kBq. It was found that for all samples the values of leakage current increased with increasing radiation dose.

46 citations