In order to explore and develop new crystal materials in the 2.7-3.0 μm band,Pr,Yb,Ho:GdScO3 crystal are successfully grown by the Czochralski method for the first time.X-ray diffraction measurement is performed to obtain powder diffraction data.Raman spectra aree measured and the vibration peaks are identified.The transmission spectrum,emission spectrum and fluorescence lifetime of Pr,Yb,Ho:GdScO3 crystal are also characterized.The center of the strongest absorption band is at 966 nm with a half-peak width of 90 nm,which comes from the transition of Yb3+:2F7/2 → 2F5/2.The absorption cross section of Yb3+ is calculated and the values at 966,973,985 nm are 0.62×10-20,0.60×10-20 and 0.58×10-20 cm2 respectively.The maximum emission peak is at 2850 nm and the half-peak width is 70 nm,the lifetimes of Ho3+:5I6 and 5I7 are measured to be 1094 and 56 μs respectively,and the emission cross section at 2850 and 2935 nm are calculated to be 3.6×10-20 cm2 and 1.21×10-20 cm2,respectively.Comparing with Yb,Ho:GdScO3 crystal,the absorption peak of Yb3+ and the emission peak are both broadened,which are related to the increase of crystal disorder.The lifetime of the lower energy level decreases significantly.Furthermore,the energy transfer mechanism between Ho3+ and Pr3+ is analyzed,and the energy transfer efficiency between Ho3+:5I7 and Pr3+:3F2+3H6 is calculated to be 99%,which is higher than those in other materials.All the results show that Pr,Yb,Ho:GdScO3 crystal is an excellent 2.7-3 μm laser material,and is easier to achieve laser output than Yb,Ho:GdScO3 crystal.
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