Tm：CaF2 and Tm;Y：CaF2 single crystals were prepared by the temperature gradient technique. The spectral properties of Tm;Y：CaF2 single crystals were investigated and compared with those of Tm：CaF2. It was demonstr...Tm：CaF2 and Tm;Y：CaF2 single crystals were prepared by the temperature gradient technique. The spectral properties of Tm;Y：CaF2 single crystals were investigated and compared with those of Tm：CaF2. It was demonstrated that codoping with Y3＋ ions could efficiently improve the spectroscopic properties. Tm;Y：CaF2 crystals have larger absorption cross-sections at the pumping wavelength, larger mid-infrared stimulated emission cross-sections, and much longer fluorescence lifetimes of the upper laser level（Tm3＋：3H4 level） than Tm：CaF2 crystals. Continuous-wave（CW） lasers around 1.97 μm were demonstrated in 4.0 at. % Tm,4.0 at. % Y：CaF2 single crystals under 792 nm laser diode（LD） pumping. The best laser performance has been demonstrated with a low threshold of 0.368 W, a high slope efficiency of 54.8%, and a maximum output power of 1.013 W.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.61422511,61635012,and 51432007)the Strategic Priority Program of the Chinese Academy of Sciences(No.XDB16030000)
文摘Tm：CaF2 and Tm;Y：CaF2 single crystals were prepared by the temperature gradient technique. The spectral properties of Tm;Y：CaF2 single crystals were investigated and compared with those of Tm：CaF2. It was demonstrated that codoping with Y3＋ ions could efficiently improve the spectroscopic properties. Tm;Y：CaF2 crystals have larger absorption cross-sections at the pumping wavelength, larger mid-infrared stimulated emission cross-sections, and much longer fluorescence lifetimes of the upper laser level（Tm3＋：3H4 level） than Tm：CaF2 crystals. Continuous-wave（CW） lasers around 1.97 μm were demonstrated in 4.0 at. % Tm,4.0 at. % Y：CaF2 single crystals under 792 nm laser diode（LD） pumping. The best laser performance has been demonstrated with a low threshold of 0.368 W, a high slope efficiency of 54.8%, and a maximum output power of 1.013 W.
