Preparation of low-loss core–clad As–Se glass fibers

Abstract

Arsenic selenide glass with the low content of residual impurities (hydrogen ⩽0.02ppm wt, oxygen <0.1ppm wt, carbon <0.5ppm wt, silicon ⩽0.1ppm wt, and metals 0.01–0.1ppm wt) is prepared. The effect of the method for producing arsenic selenide on the content of limited impurities and the optical transmission in the mid-IR range is investigated. Optical fibers of high-purity As30Se70–As40Se60 glass compositions are drawn. The minimum optical loss in unclad As35Se65 glass fiber of diameter 200μm is 70dB/km at wavelengths of 2.7 and 3.8μm. The minimum optical loss in core–clad As40Se60/As38Se62 glass fiber is 67dB/km in the 6–6.5μm spectral range, which is the best result for the core–clad As–Se glass fibers.