光学系统的保护装置—光学限制器

本文介绍了不同种类的光学限制器及其相应的机理，着重地讨论了利用双光子吸收过程的半导体光学限制特性，并对不同光波段可能的候选材料进行了讨论．     

Theoretical and experimental study of the intensity distribution in biological tissues

Based on the diffusion approximate theory （DA）, a theoretical model about the distribution of the intensity of a narrow collimation beam illuminating on a semi-lnfinite biological tissue is developed. In order to verify the correctness of the model, a novel method of measuring the distributions of the intensity of light in Intralipid-10% suspension at 650 nm is presented and ts of the distributions of the distance-dependent intensity of scattering light in different directions are made. The investigations show that the results from our diffusion model are in good agreement with the experimental results beyond and in the areas around the light source, and the distance-dependent intensity in the incident direction attenuates approximately in the exponential form. Furthermore, our theoretic results indicate the anisotropic characteristics of the intensity in different directions of scattering light inside the biological tissue.     

利用改进的Z-scan方法确定热致非线性

给出了两种改进的Ｚ－ｓｃａｎ方法．它们较通常的Ｚ－ｓｃａｎ方法具有更高的灵敏度。利用这两种方法，对溶液的热致非线性进行了测量，实验与理论符合得较好。     

A Novel Three-Dimensional Wide-Angle Beam Propagation Method Based on Split-Step Fast Fourier Transform

A novel three-dimensional wide-angle beam propagation method based on the split-step fast Fourier transform is developed. The formulation is based on the three-dimensional Helmholtz wave equation. Each propagation step is performed by utilizing both the FFT and split-step scheme. The solution of Helmholtz wave equation does not make the slowly varying envelope and one-way propagation approximations. To validate the efficiency and accuracy, numerical results for a propagation beam in a tilted step-index optical waveguide are compared with other beam propagation algorithms.     

Noncolinear Second-Harmonic Generation Pairs and Their Scatterings in Nd~(3+):SBN Crystals with Needle-Like Ferroelectric Domains

Second-harmonic generation in Nd~(3+):SBN crystal with needle-like ferroelectric with aperiodic domain structures is investigated. Two pairs of second harmonic(SH) waves appearing in lines are observed in unpoled Nd~(3+):SBN crystals with aperiodic needle-like domains. A pair of SH waves emit from the exit face, whose intensities are angle-dependent. The angular dependence is corresponding to the spatial frequency spectrum of the aperiodic domain structure. Another pair of SH waves emit from both the side surfaces, which are mainly the scattered SH waves by needle-like domain walls and obey the theory of Rayleigh scattering.     

基于傅里叶分析的超表面多维光场调控

作为一种新型的二维人工微结构,超表面在亚波长尺度上对光场的调控具有灵活性与多元性,这使得多维度、全方位的光场调控成为可能,近年来引起了广泛关注。基于傅里叶理论对胞间弱耦合超表面的设计进行理论分析,并提出收敛性条件,以弥补超表面非连续相位设计中亚波长条件不充分的不足;进一步将超表面相位调控与光场中的偏振、振幅、频率等物理性质相结合,综述了超表面在多维光场调控中的发展与应用。超表面多维光场调控不仅增大了光场调控的自由度,还推动了集成化光学设备的发展。     

新型卟啉衍生物反饱和吸收研究

利用纳秒脉冲激光下的z扫描方法对两种新型卟啉衍生物在450 nm—490 nm范围内的反饱和吸收进行了研究.通过与四苯基卟啉的比较发现，在Soret和Q吸收带之间，两种新型卟啉衍生物都具有大的反饱和吸收.采用五能级模型对实验结果进行了分析，比较了在不同波长范围内各个样品的优势.实验结果表明，在450 nm—490 nm范围内，两种新型的卟啉衍生物有着比四苯基卟啉更好的光限制应用前景. 关键词： 反饱和吸收 z扫描')" href="#">z扫描 卟啉衍生物     

光子学与光子产业

介绍了光子学的产生、发展及其应用,并对快速发展的光子产业作了展望。     

新型富勒烯C60有机钴配合物(η2-C60)(η5-RC5H4)CoPPh3 (R=H,CO2Et)的合成及性质研究

鉴于富勒烯C₆₀所具有的缺电子烯烃的特性¹以及CpCo(PPh₃)₂可与烯或炔反应生成钴杂环有机化合物,^2,3 因此我们设想如果用C₆₀代替烯、炔,令其与η⁵-RC₅H₄Co(PPh₃)₂(1) 或η⁵-RC₅H₄Co(PPh₃)(PhC≡CPh)(2)反应,则应得到一类新型的富勒烯C₆₀有机钴杂环化合物。然而与这一设想不同的是,上述反应并未得到预期的C₆₀钴杂环有机物,所得到的却是另一类新型的有机钴C₆₀衍生物(η²-C₆₀)(η⁵-RC₅H₄)CoPPh₃(3).此外,我们发现当3或2同I₂反应时,可生成C₆₀或PhC≡CPh配体被I₂置换产物η⁵-RC₅H₄Co(PPh₃)I₂(4)。     

人工光子学器件的逆向设计方法与应用(特邀)

人工设计的光子学器件在超分辨、生物传感、光通信等领域都取得了卓越的成就.传统光子学器件的设计往往是通过分析物理模型和建立数值模拟方法实现的,但是基于数值模拟方法的结构设计很大程度上依赖于经验模型,同时在结构优化的过程中需要计算大量的参数组合,因此通常只能在有限的参数空间得到次优的结果.光子学器件的逆向设计有效的解决了上...