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人体的光学二次谐波效应 总被引:4,自引:1,他引:3
在人体指纹谱的研究中我们发现人体的光学二次谐波现象。通过测试进一步观察了人体光学二次谐波效应的规律性变化,并从理论上对其机理进行了探讨。 相似文献
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简要介绍了利用非线性光学效应实现激光大气传输补偿的基本过程,分析了非线性光学效应在激光大气传输补偿中的应用现状及可能的发展趋势。最后还简要介绍了国内在这个方向上开展的工作和进展情况。 相似文献
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采用电场/温度场极化、热处理分相和超声酸处理等方法,结合透紫外-可见-近红外光谱,扫描电镜,x射线衍射和Maker条纹等测试,研究了1.6Al2O3-6.1Na2O-24.8B2O3-67.5SiO2(wt-%)准四元玻璃的二次谐波发生性能.研究表明:电场/温度场极化诱导了玻璃中二次谐波(SH)信号的产生,温度场恒定(280℃),电场强度越大,极化时间越长,SH信号越强.热处理分相使玻璃内部的微晶团聚或长大,在某些角度出现很强的SH信号.超声酸处理使玻璃表面产生一薄层微晶,在较宽角度范围出现SH信号.玻璃中存在的晶相为α-方石英. 相似文献
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四元数和超复数在二维二次非线性相位耦合分析中的应用 总被引:2,自引:0,他引:2
针对二维二次非线性相位耦合分析中的分维配对问题,本文首先对一般二维谐波信号模型进行变换,构造了符合四元数结构的新的信号模型.接着讨论了Hamilton四元数、三维超复数及"新四元数"在估计二维谐波频率中的可能性.最后根据上述模型利用特殊的三阶累积量切片分析了加性高斯有色噪声中二维二次非线性相位耦合及联合Hamilton四元数和超复数在二维二次非线性相位耦合中的应用前景.此方法避免了在复数模型的二维二次非线性相位耦合分析中构造复杂的增广矩阵,并从根本上解决了通过分维求取频率之后,频率配对中所有可能产生的错误频率对,以及有可能产生的两维频率估计精度的不平衡性.仿真实验验证了本文的理论. 相似文献
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采用荧光光谱和喇曼散射谱对非对称Ⅱ一Ⅵ族耦合多量子阱Zn1-xCdxSe/ZaSe的结构进行了表征,并对它的非线性光学特性进行了研究。实验中观察到了比较明显的量子阱荧光峰:在喇曼散射谱中观察到了分别对应于与ZnCdSe窄阱和宽阱的一级限制光学模LO1(Lowe Well)和LOI(Wide Well),及对应于ZnSe/GaAs界面的声子和等离子体的耦合模。实验发现二次谐波信号的强度随着阱间耦合的增强而增强,说明非对称量子阱(AQW)的耦合效应存在一阈值.与理论结果相一致。 相似文献
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《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1974,62(11):1511-1517
Asymptotic methods developed recently in the nonlinear wave theory and applicable to the analysis of nonsinusoidal processes are discussed. These methods are based on the assumption of sufficiently slow space-time modulation of wave parameters (shortwave approximation). The intention of this paper is neither to review all problems of asymptotic wave theory nor to give a complete bibliography. Its purpose is to show the main ideas of the methods and to present concrete procedures for the construction of the approximate solutions that correspond to the "nonlinear geometrical optics" for various types of waves. A brief classification of these processes is also given in this paper. The following questions are considered: a) the asymptotic method for quasi-stationary waves; b) a modification of this method describing slowly varying aperiodic waves (shocks and solitary waves); c) the derivation of "averaged variational principle" and its generalization for dissipative systems; d) the method of reduction of a system of equations close to the linear hyperbolic ones which is valid for nonstationary waves propagating along the characteristics; and e) the concrete problem of cylindrical finite-amplitude electromagnetic wave propagation in isotropic dielectrics. 相似文献
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本文综述了液晶非线性光学效应的一般原理,描述了液晶电动流体力学不稳定性的各种机理指出了液晶研究的现代倾向。 相似文献
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Third order nonlinear integrated optics 总被引:6,自引:0,他引:6
Stegeman G.I. Wright E.M. Finlayson N. Zanoni R. Seaton C.T. 《Lightwave Technology, Journal of》1988,6(6):953-970
The authors review progress in the application of nonlinear optical phenomena to integrated optics. Essentially all integrated optics devices such as directional couplers, Mach-Zehnder interferometers, prism couplers, etc., can be used for all-optical signal processing when at least one of the waveguiding media exhibits an intensity-dependent refractive index. Experimental and theoretical results on the operating characteristics and figures of merit of such devices, as well as a new class of phenomena based on large nonlinear changes in waveguide properties will be summarized. Also discussed are measurement techniques for evaluating waveguide nonlinearities. Progress in the implementation of other nonlinear third order interactions, such as degenerate four-wave mixing and nonlinear spectroscopy, will also be reviewed 相似文献
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关于PBT束管工艺控制的几个问题 总被引:1,自引:1,他引:0
陈晓红 《光纤与电缆及其应用技术》2003,(3):41-43
就束管工艺中由于材料特性而出现的几个问题进行了分析,并根据生产经验提出了一些改善办法。 相似文献
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液晶非线性光学和应用 总被引:3,自引:1,他引:2
描述了液晶非线性光学原理,介绍了液晶非线性光学元件的结构和制作方法,报道了我们的最新实验结果,提出了液晶非线性光学的研究方向和应用领域。 相似文献
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