Infrared emission properties of Dy3Â +-doped and Dy3Â +,Tm3Â +-codoped chalcohalide glasses

Series of 76GeS2·19Ga2S3·5AgCl (GGA) chalcohalide glasses doped with or codoped with Dy3 +, Tm3 + were prepared in this work. Systematical detection of absorption and emission spectra in the near-infrared and mid-infrared region was conducted. For the Dy3 + sole-doped GGA chalcohalide glasses, mainly due to the relatively low efficiency of pumping absorption and poor radiative transition probabilities of mid-infrared emissions, the mid-infrared emissions were hardly to be detected. Through the codoping of Tm3 + with high concentration, several intrinsical processes including the enhancement of pumping absorptive efficiency at 808 nm, cross relaxation process of Tm3 +: 3H4 + 3H6 → 3F4 + 3F4 and energy transfer process of Tm3 +: 3F4 → Dy3 +: 6H11/2 are carried out, therefore relatively strong mid-infrared emissions at about 2900 and 4300 nm have been clearly observed.