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1.
Ying-Fei Zhang Zhi-Hui Kang Yun Jiang Yury M. Andreev Konstantin A. Kokh Anna V. Shaiduko 《Optics Communications》2011,284(6):1677-1681
We report a systematic study of AgGaS2- and Al-doped GaSe crystals in comparison with pure GaSe and S-doped GaSe crystals. AgGaS2-doped GaSe (GaSe:AgGaS2) crystal was grown by Bridgman technique from the melt of GaSe:AgGaS2 (10.6 wt.%). Its real composition was identified as GaSe:S (2 wt.%). Al-doped GaSe (GaSe:Al) crystals were grown from the melt of GaSe and 0.01, 0.05, 0.1, 0.5, 1, 2 mass % of aluminium. Al content in the grown crystals is too small to be measured. The hardness of GaSe:S (2 wt.%) crystal grown from the melt of GaSe:AgGaS2 is 25% higher than that of GaSe:S (2 wt.%) crystal grown by a conventional S-doping technique and 1.5- to 1.9-times higher than that of pure GaSe. GaSe:Al crystals are characterized by 2.5- to 3-times higher hardness than that of pure GaSe and by extremely low conductivity of ≤ 10− 7 Om− 1 cm− 1. A comparative experiment on SHG in AgGaS2-, Al-, S-doped GaSe and pure GaSe is carried out under the pumps of 2.12-2.9 μm fs OPA and 9.2−10.8 μm ns CO2 laser. It was found that GaSe:S crystals possess the best physical properties for mid-IR applications among these doped GaSe crystals. GaSe:Al crystals have relatively low conductivity which have strong potential for THz application. 相似文献
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3.
R Nirmala V Sankaranarayanan K Sethupathi AV Morozkin T Geethakumary Y Hariharan 《Pramana》2002,58(5-6):1101-1104
New R
2Ti3Ge4 (R=Dy, Ho and Er) intermetallic compounds have been synthesized and characterized by X-ray diffraction and low temperature ac
magnetic susceptibility, electrical resistivity and thermoelectric power measurements were carried out. The compounds crystallize
in the parent, Sm5Ge4-type orthorhombic structure (space group Pnma) and lanthanide contraction is observed as one moves along the rare-earth series.
The changeover from paramagnetic to antiferromagnetic phase happens at low temperatures and the ordering temperature scales
with the de Gennes factor. The electrical resistivity is metallic with a negative curvature above 100 K. Thermopower displays
a weak maximum at temperatures less than 50 K signifying the possible phonon and magnon drag effects. 相似文献
4.
Tellurium and sulfur doped GaSe for mid-IR applications 总被引:1,自引:0,他引:1
Z.-H. Kang J. Guo Z.-S. Feng J.-Y. Gao J.-J. Xie L.-M. Zhang V. Atuchin Y. Andreev G. Lanskii A. Shaiduko 《Applied physics. B, Lasers and optics》2012,108(3):545-552
Centimeter-sized Te:GaSe (??10?mass%) ingots have been grown by the vertical Bridgman technique and studied to reveal the potentials for phase matching and frequency conversion. Less than 5 mass% Te-doped crystals show the hexagonal structure like ??-GaSe. Te:GaSe (??2?mass%) crystals were suitable for non-linear applications. The optimal Te-doping level between 0.1 and 0.5 mass% has been clearly observed in CO2 laser SHG experiment. The CO2 laser SHG efficiency in Te:GaSe (0.1?C0.5 mass%) is ??20?% higher than that of GaSe due to better optical quality. Phase matching conditions in Te-doped crystals have been shown to be identical with those of GaSe. 相似文献
5.
AA Ionin IO Kinyaevskiy YM Klimachev AA Kotkov AY Kozlov YM Andreev GV Lanskii AV Shaiduko AV Soluyanov 《Optics letters》2012,37(14):2838-2840
Collinear cascaded mid-IR frequency conversion in a single nonlinear optical crystal was accomplished. Concurrent collinear generation of the sum frequency of multiline fundamental band carbon monoxide laser radiation as a first frequency conversion cascade resulted in collinear difference frequency generation within the 4.3 to 4.9 μm spectral range when mixing this sum frequency radiation with the fundamental one as the second cascade in the same ZnGeP(2) nonlinear optical crystal. 相似文献
6.
首先建立了无限大晶体截面近似下的时-空4维光场和温度场耦合的倍频模型. 并在瓦级功率激光抽运下,利用解析公式和迭代方法数值模拟了BBO晶体内的倍频过程.得到了基频光和倍频光的振幅和转换效率曲线以及温度场分布,展示了温度场及光场的时间演化过程. 其次分析了抽运功率和晶体长度对转换效率和温度场的影响. 结果给出,温度分布对转换效率和光束质量都有较大影响;对热效应引起的相位失配进行补偿能够很好地改善转换效率的下降,因此必须在实际应用中加以考虑.
关键词:
倍频
温度场
BBO晶体 相似文献
7.
Investigation results on linear and non-linear optical properties, damage threshold and potential efficiencies of biaxial negative LiInS2 crystal are represented. It shows that the crystal has phase-matching and group-velocity matching in wide spectral range for second harmonic, sum- and difference-frequency generation of visible, near and middle IR lasers. The possibilities of designing middle IR optical parametric oscillator (OPO) pumped by Nd:YAG and dye lasers and specially possibility of frequency conversion with 3 um range femtosecond erbium lasers are given. 相似文献
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Resonant ultrasound spectroscopy was used to measure the elastic constants of bcc Ta0.33V0.67 over the temperature range 3.5–300?K; the results were compared to earlier measurements on C15 TaV2. The temperature dependence of the polycrystalline shear modulus is completely different in the two phases; that of the bcc phase decreases with temperature whereas that of the C15 phases increases in an anomalous fashion. This difference is consistent with a model involving doubly-degenerate levels at the X point of the Brillouin zone in the C15 phase with the Fermi level lying near the doubly degenerate level. This model accounted for the unusual behaviour of the C15 phase. Debye temperatures were determined from the ultrasonic measurements: 295?K for the C15 phase and 315?K for the bcc phase. 相似文献
9.
The basic optical property and phase-matching of new mixed AgGaGeS_4 crystal are presented. Frequency conversion, in particular the SHG of 30ns pulses of 9μm emission band of transversely excited atmospheric-pressure (TEA) CO_2 laser, is realized in AgGaGeS_4 for the first time. As high as 0.57% peak power and 0.3% external energy efficiencies, and 0.7mJ harmonic pulse energy are obtained for the 9.55μm emission line at pump intensity of 4% level of the damage threshold. 相似文献
10.