Active fluoride glasses for laser applications

The synthesis conditions of fluoride ZBLAN type glasses doped with 1, 2 or 5 mol % of Nd3+, Er3+ ions have been presented in this paper. Glasses were melted in special clean "glove box" type chamber, constructed and built in ITME, in controlled atmosphere of clean and dry nitrogen. Synthesised glasses are characterised with good homogeneity, high degree of clarifying, and with negligible tendency to crystallisation in temperature of optical fibres drawing. Investigations of spectral properties, luminescence and lifetime of active ions on excited level in the selected samples of glasses have shown their usefulness for lasers: lambda = 1.06, 1.35 mu m (Nd3+), 1.55 mu m (Er3+). Multimode fibres with core from active glass, coated with FEP Teflon layer, were drawn. At present, research works are conducted on mastering of new technology of two glass layers (core-cladding) manufactured by rotation-casting method and of all-glass optical fibres drawing.