Study on 1.8 μm emission of Tm3 + doped GeS2–Ga2S3–CsCl glasses

Tm3 + doped GeS2–Ga2S3–CsCl (GGC) chalcohalide glasses are prepared by melt-quenching method. The 1.8 μm emission of Tm3 + is investigated under the excitation of 808 nm laser diode. The ratio of the 1.8 μm emission intensity to that of the 1.48 μm (I1.8/I1.48) reaches 10.7, it is much higher than previously reported Tm3 + doped oxide glasses. With the optimized doping concentration, the 1.8 μm emission in a range of 1756 to 1876 nm shows the largest full-width-at-half-maximum (FWHM) of ~ 120 nm. The life time of Tm3 + reaches millisecond level for the present chalcohalide glasses. It is at the same level as oxide glass counterparts.