High-purity As2S1.5Se1.5 glass optical fibers

Core-clad optical fibers were fabricated from high-purity As2S1.5Se1.5 glass, and their properties were studied. The arsenic sulfo-selenide was prepared by melting a mixture of high-purity arsenic monosulfide, arsenic, and selenium. Optical fibers with core/clad diameters of 300/400 and 200/400 mum were fabricated by the double-crucible method. The minimum loss was found to be 60 +/- 20 dB/km at 4.8 mum and 200-300 dB/km between 4 and 6 mum. The numerical aperture of the fibers was 0.28. A 1.5-m-long section of the fiber transmitted 6-W CO laser radiation. The average bending strength of the 400-mum-diameter fibers was 0.8 GPa.