Zhydachevskii Y. Physical properties of the manganese-doped yttrium orthoaluminate for luminescent dosimetry of ionizing radiation.

The thesis is devoted to the problem of controlled modification of properties and ways to optimize complex oxides suitable for luminescent dosimetry of ionizing radiation on the basis of the thermally and optically stimulated luminescence phenomena. By studying the optical and luminescent properties of the manganese-doped yttrium orthoaluminate crystals (YAlO3:Mn) and the influence of radiation and thermal fields, the possibility and prospects of use of this material for luminescent dosimetry of ionizing radiation was shown. The regularities of influence of chemical composition and technological factors on the optical and luminescent properties of the Czochralski-grown YAlO3:Mn crystals were established to obtain effective crystalline phosphor YAlO3:Mn2+ suitable for luminescent dosimetry of ionizing radiation. Among the studied technological factors were: the ratio of the basic components (Y2O3/Al2O3), the composition of doping component (MnO or MnO2), the presence of non-isovalent dopants (Ca2+, Si4+, Hf4+) and the after-growth high-temperature annealing in oxidizing or reducing environment. The main dosimetric characteristics of the thermoluminescent detectors based on YAlO3:Mn2+ single crystals were established and compared with commercial detectors. Nanocrystalline and ceramic YAlO3:Mn materials were synthesized by different methods and their luminescent properties were studied to find an inexpensive and reproducible technology for manufacturing of the luminescent detectors based on this material. Comparison of the best single crystalline and ceramic YAlO3:Mn2+ detectors for detection and dosimetry of different types of photon and particle ionizing radiation was performed.