Spectroscopic properties of the glass of fluoroaluminate systems with small additives of barium metaphosphate activated with the ions of rare-earth elements

Abstract

Optical and EPR studies of fluoroaluminate glass based on usovite with small additives of barium metaphosphate (0.1–10 mol %) have been performed. The introduction of phosphates in the composition of the fluoride matrix of glass leads to a decrease in the crystallization ability but to the simultaneous shift of the edge of the transmission band into the high-energy spectral region. It was shown that for compositions with 1–2 mol % of barium metaphosphate this shift does not exceed 125 cm−1 at a transmission of not less than 60% to 1430 cm−1 (6.4 μm) for the samples with the thickness of 1 mm. It is supposed that glass containing 1.5–2.0 mol % Ba(PO3)2 is characterized by the mixed frame of glass different from the chain structure of fluoroaluminate and phosphate glass.