Dysprosium and thulium-doped chalcohalide glass fibers for 1.3 μm and S-band amplification

Summary form only given. We have prepared chalcohalide glass fibers doped with Dy³⁺ or Tm³⁺ for fiber-optic amplifiers operating at 1.3 μm and S-band windows, respectively. The optimum glass composition is 0.70 [Ge_0.25As_0.10S_0.65]-0.15 GaS₃2/-0.15 CsBr in mole fraction. Addition of CsBr and As into Ge-Ga-S glasses provided suitable resistance against the devitrification together with tremendous improvement in the spectroscopic properties. The lifetime of the 1.3 μm emission increases as much as 40 times with quantum efficiency approaching 100%. 1.48 μm emission from Tm³⁺ also showed a large increase in relative intensities with FWHM intensity of 90 nm. These glasses have potential to become an ideal gain medium for 1.3 μm and S-band amplification.