Growth and optical properties of ytterbium and rare earth ions codoped CaF2-SrF2 eutectic solid-solution(RE = Y3+,Gd3+,La3+)

• 作者: Binbin Jiang Lihe Zheng Dapeng Jiang Handi Yin Jiangang Zheng Qiuhong Yang Guofeng Cheng Liangbi Su
• 来源期刊: 稀土学报（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: SPECTROSCOPY, LUMINESCENCE AND PHOSPHORS
• 页码范围: 390-397
• 页数: 8页
• 语种: 英文

摘要

Ytterbium and rare earth ions(RE = Y,Gd,La)codoped CaF2-SrF2 single crystals(3 at％Yb,6 at％RE:CaF2-SrF2)were fabricated by temperature gradient technology(TGT).All the space groups remain the same Fm3m as that of Yb:CaF2-SrF2.The lattice parameter a,unit cell volume V,as well as bond length of Ca/Sr-F and F-F increase in the sequence of rare-earth ions radius Y3+＜ Gd3+＜ La3+.The segregation coefficients of Yb ions are 0.87 in Yb,La:CaF2-SrF2 and Yb,Gd:CaF2-SrF2,which are larger than 0.85 in Yb,Y:CaF2-SrF2 and 0.80 in Yb:CaF2-SrF2.Absorption spectra in the range of 200 and 400 nm were analysed with Yb2+contents.The absorption and emission cross-sections in the range of 900-1100 nm were determined together with fluorescence lifetime.The saturation pump density Isat,minimum pump density Imin and gain cross-section σg were analysed.Yb,La:CaF2-SrF2 has a relatively higher optical parameter(σem × τ,0.52 × 10-20 cm2·ms),lower Isat(3.68 kW/cm2)and Imin(0.50 kW/cm2)at 1038 nm indicating the potential application in high power laser.Low phonon energy of CaF2-SrF2 is 302 cm-1 which is located between those of CaF2 and SrF2 as measured by Raman spectra.It is believed that ytterbium and rare earth ions(RE = Y3+,Gd3+,La3+)codoped CaF2-SrF2 eutectic solid-solution is promising for high-power and wavelength-tunable solid-state lasers.