Spectral Analysis and Thermal Properties of Nd∶GdYAG Laser Crystal
The adsorption and fluorescence spectra of the grown Nd∶GdYAG were measured.The spectral parameters,such as oscillator strength,line strength,intensity parameter Ωt,transition probability between 4F3/2→4IJ levels,radiation lifetime,and fluorescence branching ratio,were calculated with Judd-Ofelt theory.The calculated Ωtare Ω2=(0.813±0.200)×10-20 cm2,Ω4=(3.381±0.187)×10-20 cm2,Ω6=(5.135±0.278)×10-20 cm2,respectively.Compared with Nd-doped YAG,LuAG,YVO4,and other crystals,Nd∶GdYAG crystal has a larger Ω2,showing that the addition of Gd3+increases the disorder of the host.The absorption cross-section and refractive index in the range of 300～1 200 nm were calculated and fitted.The absorption cross-section at 808 nm is 5.0 × 10-20 cm2.The refractive index at 1 064 nm is 1.80.The measured fluorescence lifetime of 4F3/2 level is 228 µs,which is close to the calculated radiation lifetime of 240 µs.The emission cross-section at 1 064 nm is 1.23× 10-19 cm2,which is close to that of Nd∶YAG crystal.Addition,at room temperature,the thermal conductivity of Nd∶GdYAG crystal is 5.992 W/(m·K),which is slightly smaller than that of Nd∶YAG and Nd∶GGG,but larger than that of Nd∶YVO4 crystal.The results show that Nd∶GdYAG is a promising new laser crystal material.
万方数据
维普
