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Information × Registration Number 0225U002136, (0124U004600) , R & D reports Title Development of fast scintillators based on rare-earth perovskites. popup.stage_title Визначення ефектів взаємодії розплавів рідкісноземельних перовскітів із Mo/W у відновних СО-вмісних середовищах. Head Sidletskyi Oleh Ts., Доктор технічних наук Registration Date 20-02-2025 Organization Institute for Scintillation Materials of National Academy of Science of Ukraine popup.description1 Development of oxide scintillation crystals based on (Y,Gd,Lu)AlO3 perovskites with accelerated run up times and decay of scintillations for detecting ionizing particles in high-energy physics experiments at colliders and in medical tomography. popup.description2 At the first stage of the work, the interaction of REAlO3 melts (where RE = Lu, Gd, Y or their mixtures) with crucible materials (W, Mo) was studied. For the first time, GdAlO3:Ce and Y0.5Gd0.5AlO3:Ce crystals grown in W crucibles in a reducing Ar+CO atmosphere were obtained by the Czochralski method. The use of tungsten crucibles is coused by their low cost: for example, the cost of Ir, from which crucibles for growing rare-earth perovskite crystals are usually made, is more than 1000 times higher than the cost of W. This allows saving more than 50% of the cost of obtaining crystals. To obtain crystals with fewer cracks, it is necessary to modernize the growth equipment by insulating them, since perovskites have low thermal conductivity (compared to garnets, the growth equipment for which were taken as a basis when creating nodes for this work). This will reduce the temperature gradient above the melt surface. Also, it is important to use a single-crystal seed of a given orientation. Since the perovskite lattice is anisotropic, it is important to orient the growth direction along the <010> crystal direction, which is most different from the others. The use of tungsten crucibles turned out to be optimal, since the latter is a cheaper alternative to Ir crucibles. Even though W inclusions were found on the surface of some crystals, they were not present in the crystal volume. Molybdenum crucibles, in turn, are much worse for use in growing REAlO3 (where RE = Lu, Gd) due to the lower melting point of Mo compared to W (2620 °C vs 3420 °C). The use of such crucibles will lead to greater contamination of the melt and, accordingly, the crystal with molybdenum inclusions, as well as to their faster degradation. Product Description popup.authors Arkhypov Pavlo V. Halenina Viktoriia V. Herasymov Yaroslav V. Kofanov Denys О. Kurtsev Daniil О. Pavlyuchenko Maryna V. Sidletskyi Oleh Ts. Sadivnycha Sofiia F. Tkachenko Serhii A. popup.nrat_date 2025-02-20 Close