LUMINESCENT PROPERTIES OF BaFBr CRYSTALS IRRADIATED WITH XENON IONS

The photoluminescent properties of BaFBr single crystals irradiated with xenon ions at a specific energy of 1.75 MeV/nucleon at a temperature of 300 K have been investigated. The crystals were grown using the Steber method, which allows for reduced oxygen impurity content. It was found that with an increase in ion irradiation fluence (F = 1·10¹⁰–1·10¹² ions/cm²), the photoluminescence intensity increases. The spectra revealed bands associated with various oxygen-vacancy centers, the presence of oxygen was also confirmed by elemental analysis performed on the BaFBr crystals. Decomposition of the spectra into Gaussian components enabled the identification of the contributions from specific types of oxygen-related defects. The results indicate the formation of color centers associated with bromine vacancies and a shift in luminescence maxima. This study contributes to the understanding of energy accumulation and relaxation mechanisms in BaFBr crystals.

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