Growth and Spectral Properties of Ho, Y∶CaF2 Crystal Grown with Porous Crucible TGT Method
DONG Jianshu, WANG Qingguo, XU Jun, XUE Yanyan, WANG Wudi, CAO Xiao, TANG Huili, WU Feng, LUO Ping
2022, 51(2):
200-207.
Asbtract
(
164 )
PDF (7234KB)
(
245
)
References |
Related Articles |
Metrics
CaF2 and SrxCa1-xF2crystals with different doping concentration of Ho3+ and Y3+ were successfully grown by the temperature gradient technique (TGT) in self-designed furnace, which can realize the synchronous growth of seven crystals with different doping concentration. The size of the grown crystals is about ϕ15 mm×55 mm, and the growth cycle is about 6 d. The spectral properties of 4%(atomic fraction)Ho, 4%Y∶CaF2 crystals were tested and analyzed. The absorption cross section at 448 nm and 643 nm were 1.13×10-20 cm2 and 0.84×10-20 cm2. J-O theory was applied to analyze fluorescence properties, the intensity parameters Ωt(t=2, 4, 6), radiative transition rates, branching ratios and radiative lifetime were calculated. Excited by 448 nm xenon lamp at room temperature, the emission cross section at 546 nm, 650 nm and 752 nm were calculated to be 10.450×10-21 cm2, 8.737×10-21 cm2 and 5.965×10-21 cm2, respectively, and the fluorescence lifetime of the Ho3+ 5F4 and 5F5 level were measured to be 33.5 μs and 17.7 μs. Excited by 640 nm LD pump at room temperature, the emission cross section at 2 031 nm and 2 847 nm were calculated to be 5.375×10-21 cm2 and 10.356×10-21 cm2, respectively, and the fluorescence lifetime of the Ho3+ 5I7 and 5I6 level were measured to be 4.37 ms and 1.85 ms. All results show that the porous graphite crucible TGT method could greatly improve the efficiency of screening the doping concentration of rare earth ions in crystals, and speed up the research process of the new laser crystal materials.
E-mail Alert
RSS
