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991.
高斯光束在外加空间调制电场的光折变晶体中的演化 总被引:1,自引:0,他引:1
研究了高斯光束在外加空间调制电场的光折变晶体中的演化,结果表明,在不同的外加调制电场作用下高斯光束的光场分布会随着外电场变化而被调制。重点研究了同相位和反相位以及相位差为π/2的高斯光束在外加空间调制电场的光折变晶体中的相互作用,在外加空间分布线性增加电场作用下出现了许多新的实用特性,通过调整外加电场分布,可以让两同相位相干光靠得更近而不发生融合,也可以让两靠得很近的反相位光束可控偏转,还可以控制相位差为π/2的两相干光束进行能量转移。这种连续变化的电场可以用阶梯分布的电场替代,为工程实现提供了可能。 相似文献
992.
993.
使用Gaussian03程序包中的“对称性匹配簇-组态相互作用”方法、在0.13—2.0nm的核间距范围内利用6-311 G(d,p)基组对7Li2(23Πu)分子的势能曲线进行了计算,同时使用最小二乘法将计算结果拟合成了解析势能函数.利用拟合出的解析势能函数并结合Rydberg-Klein-Rees方法,计算了该态的谐振频率,进而计算了该态的其他光谱常数,分别为Te=3.6701eV,De=1.0764eV,Re=0.3000nm,ωe=285.69cm-1,ωeχe=1.8351cm-1,αe=0.00942cm-1和Be=0.5340cm-1,其中光谱常数Te,De,Re和ωe的值与文献值相符很好.以得到的解析势能函数为基础,通过求解双原子分子核运动的径向Schr dinger方程,发现J=0时7Li2(23Πu)分子存在67个振动态,求出了相应于每一振动态的振动能级、振动经典转折点及转动惯量. 相似文献
994.
The effect of light noise on a Neurospora circadian clock system in the steady states is investigated. It is found that the circadian oscillations could be induced
by light noise, leading to various resonance phenomena including internal signal stochastic resonance (ISSR) and ISSR without
tuning in the system. The strength of ISSR could be significantly reinforced with the decrease of the distance of the control
parameter to the Hopf bifurcation point of the system. The fundamental frequency of noise-induced circadian oscillations almost
does not change with the increment of light noise intensity, which implies that the Neurospora system could sustain intrinsic circadian rhythms. In addition, the ISSR and ISSR without tuning could be both amplified,
suppressed or destroyed by tuning the frequency or amplitude of external signal. 相似文献
995.
Yuan Zhong-cai Shi Jia-ming 《International Journal of Infrared and Millimeter Waves》2007,28(11):987-992
In a collisional plasma, the collision frequency between electrons and neutrals may be equal to or greater than incident electromagnetic
wave frequency. The complex permittivity can not represent the dielectric property of the plasma perfectly used in the finite
difference in time domain (FDTD). Drude model is adopted to characterize a collisional plasma. Using a commercial FDTD package,
XFDTD 6.0, the electromagnetic scattering of plasma sphere is calculated. By comparison with Mie method, Drude mode is proven
to be suitable. Radar cross-section (RCS) of nonuniform plasma spheres and conductor spheres coated by plasma layer are calculated. 相似文献
996.
997.
Fu Qian-Gang Shi Xiao-Hong Li Ke-Zhi Zhang Wei Huang Min 《Applied Surface Science》2007,253(8):3757-3760
A SiC whisker-toughened SiC-CrSi2 oxidation protective coating was prepared on the surface of C/C composites by a two-step technique of slurry and pack cementation. The oxidation protective ability and thermal stress resistance of the coating exhibit the trend of increase first and decrease afterwards as the SiCw content increases from 0 to 20 wt.%. The compound effect of SiCw and CrSi2 on the oxidation protective ability of SiC coating is better than their individual ones. 相似文献
998.
In this report, we demonstrate the efficient generation of collinearly propagating photon pairs in a bulk periodically poled potassium titanyl phosphate pumped by a cw laser. The detected coincidence counts are more than 7400/s with 3.58 mW pump power in a Hanbury-Brown-Twiss-type experiment. The estimated photon pair production rate is about 0.73 MHz/mW. This is very promising for some applications, such as quantum key distribution, proof of the Bell-inequality, preparation of single photon states in broadband wave packets, Franson-type interference and so on. 相似文献
999.
Arrays of Fe0.92−xCoxP0.08 (0.22≤x≤0.78) ternary alloy nanowires were fabricated in anodic aluminium oxide templates by electrochemical deposition. The broadened peaks in transmission Mössbauer spectra and the halo in selected area electron diffraction patterns indicate that the structure of Fe0.92−xCoxP0.08 nanowires is amorphous. However, the short-range order of Fe0.92−xCoxP0.08 nanowires has a bcc structure with a [110]-preferred orientation that is parallel to the nanowires. The magnetic texture results in the magnetic moment direction of the Fe atoms being along the nanowires. The short-range order around the Fe atoms reaches a minimum at x=0.45. With increasing Co content, the average hyperfine field decreases, while the isomer shift and quadrupole splitting remain almost constant, which result from the variation of 3d and 4s electron volume density at the Fe sites. 相似文献
1000.
Shuang Zhao Fuquan Wu Haifeng Wang Weigang Zhong Xiuzhen Li Hengjing Tang Meng Shi Hongyan Deng 《中国光学快报(英文版)》2007,5(4)
The main refractive indices of calcite crystal are measured by the means of auto-collimation, and the thermo-optical coefficients are calculated. The coefficient expression of Sellmeier equation is obtained by solving Sellmeier equation strictly and the refractive indices of different wavelengths are calculated, which accord with experimental esultsery well. The measured main refractive indices of calcite at 488-nm wavelength are identical with the values obtained by Sellmeier equation. 相似文献