KDP crystals doped with Chicago Sky Blue 6B(CSB-6B) were grown by traditional lowering temperature method.The optical properties and structural perfection of KDP crystals were investigated by transmittance spectra a...KDP crystals doped with Chicago Sky Blue 6B(CSB-6B) were grown by traditional lowering temperature method.The optical properties and structural perfection of KDP crystals were investigated by transmittance spectra and high-resolution X-ray diffraction,respectively.The results indicate that CSB-6B tends to be incorporated into the pyramidal sector of KDP crystals(PyS-KDP) and lead to inclusions parallel to(101) face.Additionally,the transmittance of as-grown KDP crystals decreases as the amount of CSB-6B increases. Moreover,the rocking curves of PyS-KDP suggest that CSB-6B can deteriorate the structural perfection of PyS-KDP.展开更多
Ce-doped lithium niobate (LiNbO3) single crystals were grown from the melts with various Li/Nb molar ratios (0.750, 0.850, 0.946, 1.100, 1.250 and 1.380) by Czochralski method, while doping concentration of Ce was...Ce-doped lithium niobate (LiNbO3) single crystals were grown from the melts with various Li/Nb molar ratios (0.750, 0.850, 0.946, 1.100, 1.250 and 1.380) by Czochralski method, while doping concentration of Ce was 0.1 mol%. Infrared spectra (IR) and Ultraviolet-visible absorption spectra (UV) of the crystals were measured to investigate the location of Ce ions and defect structure in crystals. The writing time, erasing time, photorefractive sensitivity and dynamic range were measured by two-wave coupling equipment. The results showed that Ce takes the place of Li lattice site, and the LiNbO3 crystal grown from the melt with Li/Nb ratio of 1.250 is stoichiometric crystal, which has the best properties due to the synergistic effect of Ce ion and Li/Nb ratio. Also the influence of various Li/Nb ratios on the defect structure and optical properties of the crystal was reported.展开更多
Nd3+: Li3Ba2La3(MoO4)8 crystal has been grown from a flux of Li2MoO4 by the top seeded solution growth method (TSSG) and its structure was confirmed by X-ray diffraction. The polarized absorption spectra, fluore...Nd3+: Li3Ba2La3(MoO4)8 crystal has been grown from a flux of Li2MoO4 by the top seeded solution growth method (TSSG) and its structure was confirmed by X-ray diffraction. The polarized absorption spectra, fluorescence spectra and fluorescence decay curve of the crystal were measured. The main spectral parameters were calculated by the Judd-Ofelt theory and compared with other Nd-doped crystals. The broad absorption bands and the large absorption cross sections around 805 nm indicate that the crystal is very suitable for diode-laser pumping. The broad emission bands around 1060 nm show that the crystal is a potential medium for tunable and short pulse lasers. The quantum efficiency of the crystal is up to 95%, which is higher than the value for Nd3+:YVO4 and Nd3+:YAG and comparable to that of other disordered molybdate crystals. The excellent spectroscopic properties show that Nd3+:Li3Ba2La3(MoO4)8 crystal may be regarded as a potential solid state laser host material for diode laser pumping.展开更多
A Ti:sapphire crystal with a diameter of 235 mm and thickness of 72 mm was grown by the heat exchange method(HEM). The absorption intensity of the crystal at 532 nm averaged at 91%. The figures of merit(FOMs)at d...A Ti:sapphire crystal with a diameter of 235 mm and thickness of 72 mm was grown by the heat exchange method(HEM). The absorption intensity of the crystal at 532 nm averaged at 91%. The figures of merit(FOMs)at different positions of the crystal were measured and the FOM value in the central region was found to reach 90.The transmittance laser beam was intact with no obvious distortions and had only a small deformation compared with the incident laser beam. A small-signal amplification experiment was performed on the Ti:sapphire crystal and a gain of more than 6 times was achieved with a pump energy density of 1.98 J∕cm^2. These tests indicate that the 235 mm Ti:sapphire crystal has excellent optical qualities and will further improve the energy output of a 10 PW laser system.展开更多
Wavelength-dependent birefringence and dielectric anisotropy.two major optical properties of the nematie liquid crystal materials used in phase-only liquid crystal on silicon(LCOS) devices,are measured as a function...Wavelength-dependent birefringence and dielectric anisotropy.two major optical properties of the nematie liquid crystal materials used in phase-only liquid crystal on silicon(LCOS) devices,are measured as a function of operating temperatures.The dynamic phase modulation depth and threshold voltage of these phase-only LCOS devices are also measured in the corresponding temperature range and compared with theoretical predictions.The results show that the dynamic response time can he reduced significantly by an appropriate increase ol device operative temperature,while the necessary device elements,such as phase modulation depth and threshold voltage,can be maintained at the same time.展开更多
For the first time, sodium metasilicate (SMS) doped ammonium dihydrogen phosphate (ADP) crystal was grown by slow evaporation solution technique. The unit cell parameters of grown crystal were deter- mined by mean...For the first time, sodium metasilicate (SMS) doped ammonium dihydrogen phosphate (ADP) crystal was grown by slow evaporation solution technique. The unit cell parameters of grown crystal were deter- mined by means of single crystal X-ray diffraction technique. The qualitative analysis of SMS doped ADP crystal was carried out using energy dispersive X-ray and Fourier transform infrared analysis. The in- crease in optical transparency of doped ADP crystal was ascertained in the range of 200-900 nm using the UV-visible spectral analysis. The vital optical constants were evaluated using the transmittance data to explore various optical device applications of crystal. The assertive influence of SMS on mechanical and dielectric behavior of ADP crystal was investigated by means of Vickers microhardness analysis and dielectric studies, respectively. The enhancement in second harmonic generation (SHG) efficiency of SMS doped ADP crystal with reference to potassium dihydrogen phosphate (KDP) and ADP was confirmed from Kurtz-Perry SHG test. The Kerr lensing nonlinearity in SMS doped ADP crystal was identified by means of Z-scan analysis and the third order nonlinear optical susceptibility (χ3) was found to be 6.19 × 10-5 esu, which vitalizes its application for laser stabilization systems.展开更多
YPO4:Eu3+ phosphors were synthesized by solution coprecipitation method assisted by urea in the precursor reaction solution. X-ray diffraction spectral analysis showed that the samples synthesized with urea had smal...YPO4:Eu3+ phosphors were synthesized by solution coprecipitation method assisted by urea in the precursor reaction solution. X-ray diffraction spectral analysis showed that the samples synthesized with urea had smaller particle size and lower crystaUinity than those samples synthesized without urea. Moreover, the calculated strain result indicated that the Eu^3+ site in the former exhibited a lower crystal field symmetry-than that in the latter. Hence, the influence of crystal field symmetry dominated luminescence efficiency rather than crystallinity because the luminescence intensity observed in Eu0.05Y0.95PO4 synthesized with 1.0 g urea was six-fold higher than that of the as-synthesized sample. With increased concentration of Eu^3+ ion, the luminescence intensity initially increased, and then subsequently decreased as the concentration of Eu^3+ ion exceeded 12 mol.% due to concentration quenching. The optimal condition for YPO4:Eu^3+ phosphor was Eu0.12Y0.88PO4 with 1.0 g urea added in the precursor. The luminescence intensity of the optimal condition was again enhanced 1.6-fold relative to that of Eu0.05Y0.95PO4 synthesized with 1.0 g urea.展开更多
基金Supported by the State High Technology Program for Inertial Confinement Fusion and National Natural Science Foundation of China (No 59823003, 50721002)China Postdoctoral Science Foundation (No 20080441139)Youth Scientist Fund of Shandong Province (No 2004BS04022)
文摘KDP crystals doped with Chicago Sky Blue 6B(CSB-6B) were grown by traditional lowering temperature method.The optical properties and structural perfection of KDP crystals were investigated by transmittance spectra and high-resolution X-ray diffraction,respectively.The results indicate that CSB-6B tends to be incorporated into the pyramidal sector of KDP crystals(PyS-KDP) and lead to inclusions parallel to(101) face.Additionally,the transmittance of as-grown KDP crystals decreases as the amount of CSB-6B increases. Moreover,the rocking curves of PyS-KDP suggest that CSB-6B can deteriorate the structural perfection of PyS-KDP.
基金supported by the National Natural Science Foundation of China (10732100 and 10572155)
文摘Ce-doped lithium niobate (LiNbO3) single crystals were grown from the melts with various Li/Nb molar ratios (0.750, 0.850, 0.946, 1.100, 1.250 and 1.380) by Czochralski method, while doping concentration of Ce was 0.1 mol%. Infrared spectra (IR) and Ultraviolet-visible absorption spectra (UV) of the crystals were measured to investigate the location of Ce ions and defect structure in crystals. The writing time, erasing time, photorefractive sensitivity and dynamic range were measured by two-wave coupling equipment. The results showed that Ce takes the place of Li lattice site, and the LiNbO3 crystal grown from the melt with Li/Nb ratio of 1.250 is stoichiometric crystal, which has the best properties due to the synergistic effect of Ce ion and Li/Nb ratio. Also the influence of various Li/Nb ratios on the defect structure and optical properties of the crystal was reported.
基金Supported by the Natural Science Foundation of Shandong Province (No. ZR2010EQ007)
文摘Nd3+: Li3Ba2La3(MoO4)8 crystal has been grown from a flux of Li2MoO4 by the top seeded solution growth method (TSSG) and its structure was confirmed by X-ray diffraction. The polarized absorption spectra, fluorescence spectra and fluorescence decay curve of the crystal were measured. The main spectral parameters were calculated by the Judd-Ofelt theory and compared with other Nd-doped crystals. The broad absorption bands and the large absorption cross sections around 805 nm indicate that the crystal is very suitable for diode-laser pumping. The broad emission bands around 1060 nm show that the crystal is a potential medium for tunable and short pulse lasers. The quantum efficiency of the crystal is up to 95%, which is higher than the value for Nd3+:YVO4 and Nd3+:YAG and comparable to that of other disordered molybdate crystals. The excellent spectroscopic properties show that Nd3+:Li3Ba2La3(MoO4)8 crystal may be regarded as a potential solid state laser host material for diode laser pumping.
基金supported by the National Natural Science Foundation of China(Nos.61775223 and 51502321)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB1603)the Shanghai Scientific Research Project(Nos.16JC1420600 and 16DZ0503900)
文摘A Ti:sapphire crystal with a diameter of 235 mm and thickness of 72 mm was grown by the heat exchange method(HEM). The absorption intensity of the crystal at 532 nm averaged at 91%. The figures of merit(FOMs)at different positions of the crystal were measured and the FOM value in the central region was found to reach 90.The transmittance laser beam was intact with no obvious distortions and had only a small deformation compared with the incident laser beam. A small-signal amplification experiment was performed on the Ti:sapphire crystal and a gain of more than 6 times was achieved with a pump energy density of 1.98 J∕cm^2. These tests indicate that the 235 mm Ti:sapphire crystal has excellent optical qualities and will further improve the energy output of a 10 PW laser system.
基金supported by the Beijing Natural Science Foundation(No.4144076)the National Natural Science Foundation of China(Nos.61307077 and 61376083)+1 种基金the China Postdoctoral Science Foundation(Nos.2013M530613 and 2015T80080)supported by the EPSRC Platform Grant for Liquid Crystal Photonics(EP/F00897X/1)
文摘Wavelength-dependent birefringence and dielectric anisotropy.two major optical properties of the nematie liquid crystal materials used in phase-only liquid crystal on silicon(LCOS) devices,are measured as a function of operating temperatures.The dynamic phase modulation depth and threshold voltage of these phase-only LCOS devices are also measured in the corresponding temperature range and compared with theoretical predictions.The results show that the dynamic response time can he reduced significantly by an appropriate increase ol device operative temperature,while the necessary device elements,such as phase modulation depth and threshold voltage,can be maintained at the same time.
文摘For the first time, sodium metasilicate (SMS) doped ammonium dihydrogen phosphate (ADP) crystal was grown by slow evaporation solution technique. The unit cell parameters of grown crystal were deter- mined by means of single crystal X-ray diffraction technique. The qualitative analysis of SMS doped ADP crystal was carried out using energy dispersive X-ray and Fourier transform infrared analysis. The in- crease in optical transparency of doped ADP crystal was ascertained in the range of 200-900 nm using the UV-visible spectral analysis. The vital optical constants were evaluated using the transmittance data to explore various optical device applications of crystal. The assertive influence of SMS on mechanical and dielectric behavior of ADP crystal was investigated by means of Vickers microhardness analysis and dielectric studies, respectively. The enhancement in second harmonic generation (SHG) efficiency of SMS doped ADP crystal with reference to potassium dihydrogen phosphate (KDP) and ADP was confirmed from Kurtz-Perry SHG test. The Kerr lensing nonlinearity in SMS doped ADP crystal was identified by means of Z-scan analysis and the third order nonlinear optical susceptibility (χ3) was found to be 6.19 × 10-5 esu, which vitalizes its application for laser stabilization systems.
基金the National Natural Scientific Foundation of China(10874144)the Scientific Foundation of Education Department of Hunan Province,China(06C818)
文摘YPO4:Eu3+ phosphors were synthesized by solution coprecipitation method assisted by urea in the precursor reaction solution. X-ray diffraction spectral analysis showed that the samples synthesized with urea had smaller particle size and lower crystaUinity than those samples synthesized without urea. Moreover, the calculated strain result indicated that the Eu^3+ site in the former exhibited a lower crystal field symmetry-than that in the latter. Hence, the influence of crystal field symmetry dominated luminescence efficiency rather than crystallinity because the luminescence intensity observed in Eu0.05Y0.95PO4 synthesized with 1.0 g urea was six-fold higher than that of the as-synthesized sample. With increased concentration of Eu^3+ ion, the luminescence intensity initially increased, and then subsequently decreased as the concentration of Eu^3+ ion exceeded 12 mol.% due to concentration quenching. The optimal condition for YPO4:Eu^3+ phosphor was Eu0.12Y0.88PO4 with 1.0 g urea added in the precursor. The luminescence intensity of the optimal condition was again enhanced 1.6-fold relative to that of Eu0.05Y0.95PO4 synthesized with 1.0 g urea.