STUDY OF STRUCTURAL DISORDER IN CaF2 SINGLE CRYSTALS UNDER THE INFLUENCE OF IONIZING RADIATION

This paper presents the results of a study of radiation defect creation processes in Calcium Fluoride single crystals irradiated with X-rays, protons, and fast heavy ions of Xe¹³² and Bi²⁰⁹. The main method of the study is absorption spectroscopy. In the optical absorption spectra of CaF₂ samples irradiated with different types of ionizing radiation, broad intense absorption bands associated with electron and hole color centers and their aggregates are recorded. The analysis of the optical absorption spectra is performed in the Tauc and Urbach coordinates. The effect of fast heavy ion irradiation on the fundamental absorption edge and on disordering in the anion sublattice of the CaF₂ crystal is quantitatively revealed. The nature of the radiation-induced optical absorption in the 9.8 eV region induced by irradiation with Xe¹³² and Bi²⁰⁹ ions is discussed.

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