Preparation and investigation of Ge–S–I glasses for infrared fiber optics

Abstract Glass samples of [GeS x ] 90 I 10 ( x  = 1.5, 1.7, 2.0, 2.3, 2.45, 2.6) compositions were prepared, and some their thermal, optical properties as well as tendency to crystallization were investigated. The compositional dependences of glass transition temperature, volume fraction of crystallized phase and activation energy of glass formation ( E g ) have nonmonotonic character with a maximum for [GeS 2.0 ] 90 I 10 glass. Glasses of 85.8GeS 2 –14.2GeI 4 and [GeS 1.5 ] 90 I 10 compositions are identified as promising for preparation of optical fiber. For the first time, Ge–S–I glass fibers were produced. Minimum optical losses in 85.8GeS 2 –14.2GeI 4 glass fiber were 2.7 dB/m at a wavelength of 5.1 μm, and that in [GeS 1.5 ] 90 I 10 glass fiber were 14.5 dB/m at 5.5 μm.