The Yb3＋：LiGd（WO4）2 crystal with the dimension of Ф15×35 mm3 was grown by Czochralski technique. The spectroscopic characterization and fluorescence dynamics of Yb3＋ in yb3＋：LiGd（WO4）2 crystal were inve...The Yb3＋：LiGd（WO4）2 crystal with the dimension of Ф15×35 mm3 was grown by Czochralski technique. The spectroscopic characterization and fluorescence dynamics of Yb3＋ in yb3＋：LiGd（WO4）2 crystal were investigated. The yb3＋：LiGd（WO4）2 crystal exhibits a broad absorption band centered near 975 nm with the linewidths of 16 and 11 nm and maximal absorption cross-section of 3.60 × 10-20 and 2.90× 10-20 cm2 for π- and σ-polarization, respectively. The emission broadband has an FWHM of 47 and 45 nm with the emission cross sections of 3.92 × 10-20 and 3.34× 10-2o cm2 at 1020 nm for re- and or-polarization, respectively. The measured fluorescence lifetime is 398 gs. The blue light emission around 480 nm through cooperative upconversion from the de-excitation of excited Yb3＋-Yb3＋ pairs at 4 K was observed under 932-nm excitation and demonstrated.展开更多
The 0.6 at.%Pr^(3+)-doped CaF_(2)-YF_(3)crystal was successfully grown by the temperature gradient technique(TGT).X-ray diffraction analysis showed that the grown crystal still had cubic structure.The absorption spect...The 0.6 at.%Pr^(3+)-doped CaF_(2)-YF_(3)crystal was successfully grown by the temperature gradient technique(TGT).X-ray diffraction analysis showed that the grown crystal still had cubic structure.The absorption spectrum,emission spectrum,Judd-Ofelt analysis and fluorescence decay curve at room temperature were discussed.The fluorescence lifetime of Pr:CaF_(2)-YF_(3)crystal was 45.46µs,and theσem·τof ^(3)P0→^(3)H_(6) and ^(3)P0→^(3)F_(2) transitions were calculated to be 80.92×10^(−20) cm^(2)·µs and 388.7×10^(−20) cm^(2)·µs,respectively.The FWHMs are 20.1 nm and 6.8 nm,which are higher than those of Pr:LiYF_(4),Pr:LiLuF_(4),Pr:LiGdF_(4) and Pr:BaY_(2)F_(8) crystals.The results show that the Pr:CaF_(2)-YF_(3)crystal is expected to achieve 605 nm orange light and 642 nm red light laser operation.展开更多
A Sr3Yb2（BO3）4 single crystal was obtained by the Czochralski method. The structure of Sr3Yb2 （BO3）4 crystal was determined by single-crystal X-ray diffraction. The compound crystallizes in orthorhombic, space gro...A Sr3Yb2（BO3）4 single crystal was obtained by the Czochralski method. The structure of Sr3Yb2 （BO3）4 crystal was determined by single-crystal X-ray diffraction. The compound crystallizes in orthorhombic, space group Pnma with a=7.3750（8）, b=15.9265（14）, c=8.6776（9）, V=1019.25（18）3 , Mr=844.18, Z=4, Dc=5.501 g/cm3 , λ（MoKa）=0.71073, μ= 33.835 mm-1 , F（000）=1480, the final R=0.0339 and wR=0.0907 for 1090 observed reflections with I〉2σ（I）. The structure features a three-dimensional framework composed of isolated BO3 planar triangles bridged by YbO8 and SrO8 polyhedra. The Sr2＋ and Yb3＋ occupy statistically three independent sites with a Cm and two C1 local symmetries.展开更多
In this study, sludge from the aluminum profile factory and pyrophyllite were used as major raw materials to prepare mullite. Through determining optimum formula, the optimum calcination temperature and optimum temper...In this study, sludge from the aluminum profile factory and pyrophyllite were used as major raw materials to prepare mullite. Through determining optimum formula, the optimum calcination temperature and optimum temperature retention time as well as the effects of BaF2 mineralizer on the crystal structure, microstructure and properties of mullite were studied and the optimum BaF2 mineralizer dosage was determined. With XRD and SEM methods, the crystal structure and microstructure of each sample were characterized. With Rietveld Quantification method, crystal phase content in each sample was determined and properties of each sample were tested. Based on the comprehensive analysis result, it was determined that optimum BaF2 dosage was 0.5%, the fairly good calcination temperature was 1550 ℃, and the corresponding mullite solid solution content was 95.8%.展开更多
基金National Natural Science Foundation of China(61575212)Key Research Project of the Frontier Science of the Chinese Academy of Sciences(QYZDB-SSW-JSC022)
基金Support by the National Natural Science Foundation of China(No.60808033)train object program of Jiangxi Province Young Scientists,Natural Science Foundation of Jiangxi Province(No.2011BAB206029,2010GQS0064 and 2008GZW0012)excellent young academic talent program of Jiangxi University of Finance and Economics
文摘The Yb3＋：LiGd（WO4）2 crystal with the dimension of Ф15×35 mm3 was grown by Czochralski technique. The spectroscopic characterization and fluorescence dynamics of Yb3＋ in yb3＋：LiGd（WO4）2 crystal were investigated. The yb3＋：LiGd（WO4）2 crystal exhibits a broad absorption band centered near 975 nm with the linewidths of 16 and 11 nm and maximal absorption cross-section of 3.60 × 10-20 and 2.90× 10-20 cm2 for π- and σ-polarization, respectively. The emission broadband has an FWHM of 47 and 45 nm with the emission cross sections of 3.92 × 10-20 and 3.34× 10-2o cm2 at 1020 nm for re- and or-polarization, respectively. The measured fluorescence lifetime is 398 gs. The blue light emission around 480 nm through cooperative upconversion from the de-excitation of excited Yb3＋-Yb3＋ pairs at 4 K was observed under 932-nm excitation and demonstrated.
基金supported by the National Natural Science Foundation of China(Grant Nos.61805177,61861136007,and 61621001).
文摘The 0.6 at.%Pr^(3+)-doped CaF_(2)-YF_(3)crystal was successfully grown by the temperature gradient technique(TGT).X-ray diffraction analysis showed that the grown crystal still had cubic structure.The absorption spectrum,emission spectrum,Judd-Ofelt analysis and fluorescence decay curve at room temperature were discussed.The fluorescence lifetime of Pr:CaF_(2)-YF_(3)crystal was 45.46µs,and theσem·τof ^(3)P0→^(3)H_(6) and ^(3)P0→^(3)F_(2) transitions were calculated to be 80.92×10^(−20) cm^(2)·µs and 388.7×10^(−20) cm^(2)·µs,respectively.The FWHMs are 20.1 nm and 6.8 nm,which are higher than those of Pr:LiYF_(4),Pr:LiLuF_(4),Pr:LiGdF_(4) and Pr:BaY_(2)F_(8) crystals.The results show that the Pr:CaF_(2)-YF_(3)crystal is expected to achieve 605 nm orange light and 642 nm red light laser operation.
基金Supported by the National Natural Science Foundation of China (51002152)the Natural Science Foundation of Fujian Province (2010J05125)
文摘A Sr3Yb2（BO3）4 single crystal was obtained by the Czochralski method. The structure of Sr3Yb2 （BO3）4 crystal was determined by single-crystal X-ray diffraction. The compound crystallizes in orthorhombic, space group Pnma with a=7.3750（8）, b=15.9265（14）, c=8.6776（9）, V=1019.25（18）3 , Mr=844.18, Z=4, Dc=5.501 g/cm3 , λ（MoKa）=0.71073, μ= 33.835 mm-1 , F（000）=1480, the final R=0.0339 and wR=0.0907 for 1090 observed reflections with I〉2σ（I）. The structure features a three-dimensional framework composed of isolated BO3 planar triangles bridged by YbO8 and SrO8 polyhedra. The Sr2＋ and Yb3＋ occupy statistically three independent sites with a Cm and two C1 local symmetries.
基金Supported by the Fujian Provincial Development and Reform Commission
文摘In this study, sludge from the aluminum profile factory and pyrophyllite were used as major raw materials to prepare mullite. Through determining optimum formula, the optimum calcination temperature and optimum temperature retention time as well as the effects of BaF2 mineralizer on the crystal structure, microstructure and properties of mullite were studied and the optimum BaF2 mineralizer dosage was determined. With XRD and SEM methods, the crystal structure and microstructure of each sample were characterized. With Rietveld Quantification method, crystal phase content in each sample was determined and properties of each sample were tested. Based on the comprehensive analysis result, it was determined that optimum BaF2 dosage was 0.5%, the fairly good calcination temperature was 1550 ℃, and the corresponding mullite solid solution content was 95.8%.
