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81.
利用表面放电光泵浦技术,研制了重频XeF(C-A)激光器,运行频率达到10 Hz。研究了运行频率、气体流量对激光输出能量稳定性的影响,分析了影响输出稳定性的主要因素,实验结果表明,提高气流量可有效改善重频输出能量的稳定性。同时,还给出了优化实验条件下不同运行频率连续20个脉冲较为理想的输出结果。运行频率分别为1,2,5 Hz时,输出能量稳定性较好,输出能量大于4.0 J;气流量大于53 L/s时,10 Hz重频运行的输出稳定性已显著提高,平均输出能量也达到1.8 J。 相似文献
82.
LOSEV V F PANCHENKO Yu N DUDAREV V V IVANOV N G KONOVALOV I N PAVLINSKY A V PUCHIKIN A V 《中国光学》2011,4(1):1-8
研究了脉冲宽度为25~40 ns的放电脉冲XeCl准分子激光器的工作参数。结果显示,激光器产生的脉冲能量为0.2~0.7 J,重复频率为100 Hz,表明在泵浦功率为2.8~3.3 MW/cm3时,激光器实现了2.6%的激光效率和3.8%的本征效率。 相似文献
83.
利用飞秒时间分辨荧光亏蚀光谱技术,研究了噁嗪750激光染料分子在典型的醇类溶剂中超快动力学过程.实验发现两个超快动力学过程:飞秒量级的快速弛豫过程和皮秒量级的慢速弛豫过程.快速弛豫过程来源于分子内振动能量再分配(IVR)和溶剂分子超快惯性弛豫动力学过程,而慢速弛豫过程对应于溶剂化的扩散分子弛豫动力学过程.实验结果表明慢速弛豫过程的时间常数随醇溶剂分子间氢键键能的增强而增大. 相似文献
84.
S. Boag E. Babcock K.H. Andersen M. Becker T.R. Charlton W.C. Chen R.M. Dalgliesh S.D. Elmore C.D. Frost T.R. Gentile R. Lopez Anton S.R. Parnell A.K. Petoukhov M.W.A. Skoda T. Soldner 《Physica B: Condensed Matter》2009,404(17):2659-2662
We discuss the development and characterisation of a new in situ spin exchange optical pumping (SEOP) based 3He neutron spin filter polarisation device. We present results from a recent test of the prototype system developed with the Institut Laue-Langevin. The polariser was installed on the polarised reflectometer CRISP at ISIS in the analyser position. The 3He was pumped continuously in situ on the beamline. The system also integrated a 3He adiabatic fast passage spin flipper that allowed reversal of the 3He and therefore neutron polarisation state, allowing for measurement of all four polarisation cross-sections. The system was run for a number of days reaching a 3He polarisation of 63%. 相似文献
85.
Wai Tung Lee Xin Tong Dennis Rich Yun Liu Michael Fleenor Akbar Ismaili Joshua Pierce Mark Hagen Jonny Dadras J. Lee Robertson 《Physica B: Condensed Matter》2009,404(17):2670-2672
In recent years, polarized 3He gas has increasingly been used as neutron polarizers and polarization analyzers. Two of the leading methods to polarize the 3He gas are the spin-exchange optical pumping (SEOP) method and the meta-stable exchange optical pumping (MEOP) method. At present, the SEOP setup is comparatively compact due to the fact that it does not require the sophisticated compressor system used in the MEOP method. The temperature and the laser power available determine the speed, at which the SEOP method polarizes the 3He gas. For the quantity of gas typically used in neutron scattering work, this speed is independent of the quantity of the gas required, whereas the polarizing time using the MEOP method is proportional to the quantity of gas required. Currently, using the SEOP method to polarize several bar-liters of 3He to 70% polarization would require 20−40 h. This is an order of magnitude longer than the MEOP method for the same quantity of gas and polarization. It would therefore be advantageous to speed up the SEOP process. In this article, we analyze the requirements for temperature, laser power, and the type of alkali used in order to shorten the time required to polarize 3He gas using the SEOP method. 相似文献
86.
光磁共振实验中扫场和水平场关系的探究 总被引:1,自引:0,他引:1
光泵磁共振实验中,在磁共振信号观察时,常常会有光抽运信号同时出现的现象,这严重影响了实验的有效观察和准确测量。本文阐述了取合适的扫场和水平场的大小的关系,从而避免实验过程中磁共振信号和光抽运信号的同时出现,以确保实验的精准。 相似文献
87.
D.J.-Y. Marion P. Berthault H. Desvaux 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,51(3):357-367
When a system composed of dissolved laser-polarized xenon with negative spin temperature is put inside a high field NMR magnet,
a series of spontaneous maser emissions can be observed. We report here their spectral and temporal features using a processing
model derived from the solution of the Bloch equations in the presence of radiation damping. We show, in particular, that
by combining Fourier transformation and squared modulus, a parameter allowing the characterization of the burst of transverse
magnetization can be determined. This parameter is shown to be correlated with the radiated energy. Moreover, this processing
clearly reveals features which can probably be assigned to effects resulting from distant dipolar fields. Finally, the analysis
of the experimental data reveals an unexpected behavior of the 129Xe transverse self-relaxation. 相似文献
88.
研究了LD抽运的单纵模Cr,Tm,Ho∶YAG微片激光器,激光器厚度为1?mm,在用波长785?nm的LD进行端面抽运时,激光器阈值为1060?mW,单纵模激光最大输出功率为31?mW. 对激光器输出功率随温度变化特性进行了研究,验证了CTH∶YAG晶体的温度敏感性. 还研究了激光器的温度调谐特性,实验测得激光器的温度调谐系数为14?GHz/℃.
关键词:
激光光学
CTH∶YAG微片激光器
LD抽运
单纵模运转 相似文献
89.
T. Saiki S. Motokoshi K. Fujioka H. Fujita C. Yamanaka 《Optics Communications》2009,282(13):2556-2984
Laser pulses with high repetitive rate generated from a Q-switch microchip Nd:YAG oscillator were amplified by Active mirror composed of Nd/Cr:YAG ceramic pumped by CW arc-lamp. The laser pulses were amplified, and saturation of averaged output laser power was observed. Repetitive ratio of injected laser pulses was changed from 20 to 100 kHz. Averaged output laser power and gain were measured, and gain coefficient and power-extraction efficiency were evaluated. Output laser power was calculated and compared to experimentally measured one, and the calculated results are consistent with the experimental ones. For amplification of laser pulses with high repetitive ratio, this laser material can realize very high laser gain with low pumping power density and high optical-optical conversion efficiency under CW-lamp-light pumping. 相似文献
90.