Saint Petersburg Mining University, Saint Petersburg, Russia:

K. G. Karapetyan, Head of General Chemistry Department, Doctor of Technical Sciences, Associate Professor, e-mail: karapetyan_kg@pers.spmi.ru
O. V. Denisova, Associate Professor at the Department of Electronic Systems, Candidate of Chemical Sciences, Associate Professor, e-mail: denisova_ov@pers.spmi.ru

The rare-earth element of neodymium is used as a doping agent for a variety of alloys, as the base element for super magnets and in cryogenic industry. Inorganic glass industry represents a separate application for neodymium oxide. Having a high quantum yield of luminescence, such glasses are essential for the production of high-power optical quantum generators. Fluorophosphate glasses have a complex composition, specific physicochemical properties and spectral characteristics, and demonstrate specific matrix forming patterns when modifiers or glass forming agents are introduced. The current structural description of fluorophosphate glasses is lacking, which gives relevance to further studies into the structure of Ba(PO₃)₂ based pseudobinary glass system and barium fluoroaluminate. Microadditions of neodymium oxide were introduced as an activator during glass synthesis. Such glasses can be used as laser material. The authors examined the absorption and luminescence spectra of glass specimens containing neodymium. It is shown that fluorophosphate glasses are structurally heterogeneous systems that contain two typical activator coordination environments; introduction of fluorides in Ba(PO₃)₂ glass leads to neodymium ion segregation in the phosphate glass matrix. Specimens of crystallization resistant optical glass have been obtained. The paper describes optimum compositions of neodymium activated fluorophosphate glasses that retain the advantages of phosphate glass systems while shorter neodymium luminescence lifetimes have no noticeable impact on the glass performance.

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