Tm3t-Doped Chalco -halide Glass for Optical Amplifiers at 1.22 and 1.47？m

50GeSe2–25In2Se3–25CsI chalcohalide glass was prepared with the addition of Tm3t in 0.1–1.0wt% concentrations. Radiative parameters evaluated by the Judd–Ofelt analysis suggest a strong covalence nature of the host. Emissions peak at 1.22 and 1.46 m were observed with the 808nm laser excitation. The 1.22 m one is attributed to the Tm3t:3H5 !3H6 transition. The Raman spectra of the host suggest that the I-rich local environment of Tm3t promotes the strong 1.22 m emission. The emission intensity comes to the maximum at Tm3t concentration of 0.7 and 0.5 wt% for the 1.22 and 1.47 m emissions respectively. In addition, its potential application as the host material for novel optical amplifiers was discussed.