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Information × Registration Number 0220U100981, 0119U001352 , R & D reports Title Physical and technological foundations for creation of ceramic MgO-RE2O3 (RE: Y, La, Lu) nanocomposites of Irtran class for middle IR-region popup.stage_title Head Tolmachov Oleksandr V., Доктор фізико-математичних наук Registration Date 30-01-2020 Organization Institute for single crystals NASU popup.description2 The project aims to establish the conditions for obtaining high-quality laser ceramics Nd:YAG over a wide range of activator concentrations. The influence of Nd3+ on the consolidation processes of ceramics has been investigated. The effective diffusion rate of Nd3+ ions in the polycrystalline YAG matrix was experimentally determined as 1.5×10-15 m2/s. It was found that the doping of YAG by Nd3+ ions leads to an increase in the lattice parameter. Influence of neodymium concentration on the laser generation characteristics of Nd:YAG ceramics has been investigated. With a concentration СNd>2 at.% degradation of the laser characteristics of ceramics is observed due to a significant increase in the number of pair centers of neodymium and related luminescence concentration quenching. In ceramics 1-2 at.% Nd3+:YAG efficiency value ηslope≈68% achieved. A new method for quantifying the porosity of transparent materials has been proposed. The method is based on the determination of the pore size distribution using experimental measurements of the pore sizes determined from the cross-section using the example of transparent ceramics Nd:YAG. Influence of compact mesostructure on porosity, optical properties and laser characteristics of transparent Nd:YAG ceramics were studied. Despite that changes in the microstructure of compacts annealed at different temperatures were marginal, ceramic samples obtained at 1750°C differ significantly in porosity, optical transmission, and laser characteristics. Compacts annealed at 600°C have been shown to have an optimum mesostructure that promotes uniform compaction (mean pore size is 50 nm). Nd:YAG ceramics prepared using such compacts have a residual porosity of 0.001 vol.%, which provides a laser generation efficiency of 67% at a wavelength of 1.06 μm. Product Description popup.authors Bovda Vira O. Budnikov Oleksandr T. Vovk Olena O. Vorona Igor O. Grin Leonid O. Dobrotvorska Mariya V. Doroshenko Andrii H. Korshikova Tetiana I. Kryzhanovska Oleksandra S. Matvieievska Neonila A. Mateichenko Pavlo V. Nizhankovskiy Sergiy V. Parkhomenko Sergij V. Safronova Nadiia A. Tolmachov Oleksandr V. Yavetskiy Roman P. popup.nrat_date 2020-04-02 Close