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311.
The optical limiting effect based on stimulated Brillouin scattering (SBS) in a nonlinear medium was investigated. We numerically treated the nonlinear propagation process with a theoretical model, which includes the spontaneous nature of the initiation of SBS, and obtained optical limiting effect in the process. Energy limiting, pulse reshaping and stabilization have been demonstrated on SBS mechanism with the nonlinear medium CCl_4. The input optical signals were Nd:YAG nanosecond laser pulses with width varying from 16ns to 7ns then to 2ns, the relationship between the transmitted signal and launched pump signal was shown. In the experimental regime, the most stable pulse and a superior energy stabilization of the transmitted pulse were obtained when the laser pulse-width became as short as 2ns. For the energy variation of laser pulses in a wide range of 14-88mJ, the output energy was limited in a quite narrow range 4.5-5.5mJ. 相似文献
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313.
Kong Hong Jin Lee Jae Yong Shin Yun Sup Byun Jae Oh Park Hee Su Kim Hyogun 《Optical Review》1997,4(2):277-283
Beam recombination characteristics were numerically investigated in array laser amplification using stimulated Brillouin scattering phase conjugation. To clarify the effect of piston errors due to imperfect phase locking, spatial intensity profiles of the beam recombination output were calculated in both the near and the far field on the basis of Rayleigh-Sommerfeld diffraction theory. The analyses indicate that piston errors are seriously detrimental to the quality of a beam recombination output and should be eliminated by a proper phase locking. It is also found that the gap between the beam splitting-combining wedges has a negligible effect.Presented at 1996 International Workshop on Interferometry (IWI ‘96), August 27-29, Saitama, Japan. 相似文献
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非相干光作用下的Ce:BaTiO3自泵浦相位共轭镜特性 总被引:1,自引:0,他引:1
地Ce:BaTiO3晶体的自泵浦相位共竟然非相干光作用下自泵浦相位共轭反射率增强的特性进行了研究。实验是在He-Ne激光产生稳态自泵浦相位共轭输出后,用非相干光平行c轴照射来获得这一增强特性的,当水平移动非相干光入射位置,发现有两个区域非相干光作用能使相位共轭反射率增加,本文对此进行了相应的分析和讨论。 相似文献
316.
Dependence of Stokes dynamics in stimulated Brillouin scattering generated in optical fibers on the pump power, the nonlinear refractive index, the fiber length, and the feedback powers of the pump and the Stokes is numerically analyzed. The Stokes power fluctuation becomes complicated and chaotic as the nonlinear refractive index and the input pump power increase in a fiber of sufficient length. The Stokes dynamics is less complicated and the chaotic region decreases in a pump power-reflectivity domain in a short fiber. The chaotic behavior appears without regular tendency in relation to the feedback power. Taking into account the pump feedback, the chaotic region expands and some Stokes behaviors are different in the PP-R domain graph, compared with the case with the Stokes feedback alone, although this feedback does play an essential role in Stokes dynamics. 相似文献
317.
区间数的标准表示及其四则运算法则与泛灰数的内在联系 总被引:2,自引:0,他引:2
在回顾泛灰数四则运算法则基础上,给出了区间数的标准表示,论述了标准区间数的四则运算法则与泛灰数的内在联系及其应用前景. 相似文献
318.
利用瞬态包含泵浦抽空的SBS理论模型对独立双池受激布里渊散射系统进行数值模拟,给出了能量转换效率随泵浦功率密度的变化规律。实验验证,理论值与实验结果相吻合。 相似文献
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New parameters which separately take into account the effects of elastic anisotropy and phonon dispersion on the lattice specific
heat in the case of fcc metals have been evaluated. A new graded mesh method which uses 162-direction approximation in (1/16)
part of the Brillouin zone has been developed to evaluate the two new parameters. 相似文献