2.00 μm Emission Properties of Tm3+/Ho3+ Co-doped Chalcohalide Glasses

2 μm laser has many potential applications on the medical surgery, laser radar, and pollution monitoring etc. Tm3+ and Ho3+ ions co-doped 70GeS2-20In2S3-10CsI chalcohalide glasses were synthesized by vacuumed melting- quenching technique. The DSC curves and Raman spectra showed that these glasses had good thermal stability and low phonon energy, respectively. The absorption and emission characteristics were evaluated with an emphasis on the 2.00 μm fluorescence from Ho3+: 5I7→5I8 transition. Under 808 nm excitation, the infrared emission bands extending from 1.80 μm to 2.10 μm can be seen on the emission spectra of the Tm3+ and Ho3+ ions co-doped glasses. This broad emission was consisted of two emission bands centered at 1.86 and 2.00 μm, corresponding to the optical transitions Tm3+:3F4→3F5 and Ho3+:5I7→5I8, respectively. At fixed Tm3+ ions concentration, the intensity of 2.00 μm emission increased with Ho3+ ions concentration increasing from 0.05mol% to 0.125mol%. The enhanced emission of Ho3+ ions gives another route to obtain the 2.00 μm infrared laser.