柱面透射光栅的衍射特性

从理论上分析了较高空间频率的柱面透射光栅的衍射特性，在不作近似的条件下，用计算机模拟出了不同曲率半径的柱面透镜组成的柱面透镜组成的柱面透镜光栅的夫琅和费衍射特性，得出了共衍射光强的分布规律。光学实验给出了由光学塑料制成的空间频率为１０ｌｐ／ｍｍ的柱面透射光栅的衍射光强分布。计算机模拟结果与光学实验结果吻合。     

新型非线性光学晶体Ca4RO(BO3)3的研究进展

作为新型非线性光学材料,钙－稀土硼酸盐晶体Ｃａ４ＲＯ（ＢＯ３）３（Ｒ－Ｌａ＾３＋、Ｎｄ＾３＋、Ｓｍ＾３＋、Ｇｄ＾３＋、Ｙ＾３＋、Ｅｒ＾３＋、Ｔｂ＾３＋、Ｌｕ＾３＋）近来引起了广泛的重视,该系列晶体属非中心对称的单斜晶系,空间群Ｃｍ。本文综术字上述晶体的结构和生长研究的进展,总结了晶体的线性光学／非线性光学性能以及要晶体的激光自倍频性能,指出这些晶体在非线性光学领域潜在的应用前景。     

受激拉曼散射阈值光强的测定

本文提出一种测量受激拉曼散射阈值光强的方法,利用光学多道分析仪的递增延迟时间功能控制调Q开关,改变输出的激光光强以达到测量阈值光强的目的。这种方法适用于对激光光强表现出阈值特性的物理量的测量。     

自聚焦透镜列阵象平面上照度分布的分析

研究了自聚焦透镜及其列阵象平面上的照度分布。讨论只限于近轴射线单位放大率成象的条件下。一列和二列的自聚焦透镜列阵在场扫描和线扫描光学成象系统中,象面上光强分布将有所不同。因此,我们作了分析,并对某些样品进行了测量。     

通过多圆孔衍射、干涉同时调控实现冷分子（或冷原子）囚禁的光学偶极阱

基于通过单圆孔衍射产生实现冷分子（或冷原子）光学囚禁的光阱,考虑多光束干涉因子及衍射因子的同时调控,研究单色平面波通过多圆孔产生实现冷分子（或冷原子）光学囚禁的光阱。首先运用圆孔衍射理论分析讨论了光学偶极阱的光强分布、光学势及偶极力,紧接着联想并推广到处于同一条直线上多孔（相邻两孔之间距离相等）的情况。通过类比（如类比光栅衍射）研究与推导,得到了单圆孔衍射时垂直于光轴平面上的光强分布公式,并进一步得到了多圆孔衍射的公式。导出了光强分布与光学系统参量（如照明光波的波长、小孔的孔径）间的解析关系,通过编程成功地在DTP平台上演示了出来。该方案将单圆孔实现原子囚禁进行了推广,在冷分子物理、原子光学、分子光学和量子光学等领域中有着广阔的应用前景。     

X射线激发Ce^3＋掺杂硼酸盐玻璃的闪烁发光

实验研究了Ｃｅ＾３＋掺杂６４Ｂ２Ｏ３－３６ＢａＯ,７５Ｂ２Ｏ３－２５Ｌａ２Ｏ３玻璃的闪烁发光。在８０ｋＶ加速电压、阳极电流为５ｍＡ的高能Ｘ射线激发下闪烁光强为同要条件下闪烁晶体Ｎａｌ（Ｔｌ）的３％～４％。对影响闪烁光输出的因素进行了分析。结果表明,Ｃｅ＾３＋的自吸收和Ｃｅ＾４＋离子的荷移吸收是降低闪烁光输出的主要因素;含镧硼硅酸盐玻璃系统可作为发展高密度玻璃有希望的系统;闪烁玻璃的制备技术对提高闪     

醌构稠杂环化合物三阶非线性光学性质的研究

用三维简并四波混频实验研究了所合成的４种萘醌并噻唑，四氧二苯并噻蒽化合物的三阶非线性光学性质。上对测量法测得样品溶液的χ＾（３）≌４×１０＾３ｅｓｕ，分子的三阶超级极化率γ≌４×１０＾－３１ｅｓｕ。分析了分子结构对三阶非线性光学性质的影响。     

二元光学在强激光波面整形中的应用

文章首先介绍了二元光学波面整形器件的理论基础。在分析GS、YG等正反迭代算法存在问题的基础上,提出三种优化算法,即全局/局部联合搜索算法（GLUSA）、爬山-模拟退火混合算法及多分辨率的混合优化算法。以惯性约束核聚变中光束匀滑为例,进行了二元光学器件的位相设计,获得了良好的位相结构与焦斑性能。采用旋转镂空掩膜板制作了准连续位相器件,并利用CCD与多种光强衰减片进行焦斑光强测量。实验结果表明：获得了较好的顶部均匀性、陡边、小旁瓣、高主瓣能量利用率以及光斑中心没有锐脉冲的光强分布。     

全氟羧酸离子交换膜内化铅超微粒的光学非线性研究

在全氟羧酸阳离子交换膜中制备出不同颗粒尺寸的ＰｂＳ超微粒，并由吸收光谱及电镜测量结果获得证实。用习秒激光脉冲对ＰｂＳ超微粒复合膜进行了分辨光克尔效应测定，发现ＰｂＳ超微粒具有三阶光学非线性，三阶光学非线性极化率Ｘ＾（３）约为１０＾－１２ｅｓｕ，光克尔效应时间小于１６５ｆｓ，并且发现ＰｂＳ超微粒的光学非线性随着超微粒颗粒尺寸的减小而增大，显示出量子限域效应对于超微粒子光学非线性的贡献。     

偏光应力仪校准技术发展概况

偏光应力仪广泛用于玻璃、塑料等透明材质的内部应力测量.该仪器的校准长期以来一直难以实施,本文介绍了基于光强法的光学相位延迟的量值复现原理、装置,并介绍了光学相位延迟量值的传递过程及其相关问题.     

Optical bistability in BaTiO3

In this paper experimental results concerning the optical bistability of a ferroelectric monocrystal of BaTiO₃ are presented. Two laser beams were used to interact with the monocrystal which resulted in the bistability of the intensity of the transmitted wave. This was achieved without the application of any optical resonator. The feedback was provided by the electronic system through a mechanism typical to all photorefractive materials.     

Optical bistability of surface plasmon polaritons in nonlinear Kretschmann configuration

Optical bistability based on surface plasmon polaritons in the Kretschmann configuration involving a Kerr nonlinear medium is described by analytical solutions. The conditions of forming the optical bistability with different parameters are explored. The resonant angle of surface plasmon polaritons varying with the incident light intensity also generates the phenomenon of bistability. The system could form optical bistability with the special thickness of the metal film and incident angle. This kind of system has potential application in all-optical networks.     

Optical bistability and multistability driven by external magnetic field in a dielectric slab doped with nanodiamond nitrogen vacancy centres

Abstract

The theoretical investigation of controlling the optical bistability (OB) and optical multistability (OM) in a dielectric medium doped with nanodiamond nitrogen vacancy centres under optical excitation are reported. The shape of the OB curve from dielectric slab can be tuned by changing the external magnetic field and polarization of the control beam. The effect of the intensity of the control laser field and the frequency detuning of probe laser field on the OB and OM behaviour are also discussed in this paper. The results obtained can be used for realizing an all-optical bistable switching or development of nanoelectronic devices.     

Opto-electronic Bistable Devices for Image Processing

Several opto-electronic bistable devices with twisted nematic liquid crystals are designed and used for image processing. The optical bistability characteristics of liquid crystals are used for two types of light valve, those with array structure and parallel operation and those with single cell with sequential operation. Experimental studies demonstrate the application of these opto-electronic bistable devices in important operations currently used in image processors, such as intensity limiting for contrast improvement and noise elimination, contour accentuation for pattern recognition, linear and nonlinear optical filtering (in spatial and spectral domains), incoherent-to-coherent image conversion and logic operations.     

Optical bistability and multistability in an open ladder-type atomic system

A novel scheme is proposed for controlling the optical bistability and multistability in an atomic system. In an open ladder-type three-level atomic system, it is shown that, by adjusting the ratio between atomic injections and exit rates from the cavity, the intensity threshold of optical bistability can be controlled. The effect of incoherent pumping field and spontaneously generated coherence (SGC) on optical bistability for different values of exit rates is also discussed. It is found that SGC makes the medium phase dependent, so the optical bistability and multistability threshold can be controlled via relative phase between applied fields. Moreover, it is shown that the optical bistability can be switched to optical multistability, which is favorable for the next generation of all-optical systems and quantum networks.     

Optical bistability in BaTiO3

In this paper experimental results concerning the optical bistability of a ferroelectric monocrystal of BaTiO₃ are presented. Two laser beams were used to interact with the monocrystal which resulted in the bistability of the intensity of the transmitted wave. This was achieved without the application of any optical resonator. The feedback was provided by the electronic system through a mechanism typical to all photorefractive materials.     

Intrinsic optical bistability in doped polymer

One of the most interesting and applicable effects of nonlinear optics is optical bistability. This phenomenon is exhibited by certain resonant optical structures where it is possible to have two stable steady transmission states for the device, depending on the history of the input. Such a bistable device may be useful for optical computing elements as a result of its memory characteristics. Optical bistability behaviour is usually observed by inserting a nonlinear matter inside a Fabry–Perot interferometer. But in this study, it was shown that this can be achieved without the application of any optical resonator. Two laser beams were used to interact with the photorefractive media (doped PMMA polymer) which resulted in the bistability of the intensity of transmitted wave. Feedback was provided by a periodic grating created in the photorefractive polymer PMMA.     

Mirrorless optical bistability in a semiconductor-doped-glass plate as a result of oblique incidence

A procedure to obtain optical bistability in a third-order nonlinear film (or parallel plate) of low refractive index without any external mirrors is investigated both theoretically and experimentally. If an s-polarized light is incident obliquely at a large angle of incidence on the film, the generation of optical bistability can be expected because of the resulting increase in the reflectivity at the surfaces. Arigorous analysis of the stationary transmission characteristics of the nonlinear film is done for both positive and negative nonlinear coefficients with a plane-wave model. In the experimental demonstration, a CdS(x)Se(1-x)doped glass (Hoya Y-52) plate and a cw Ar(+) laser are used as the nonlinear material and the light source, respectively. It is shown that three operations of optical bistability, optical limiting, and differential gain can be easily obtained through adjustment of the angle of incidence as an initial detuning. The measured nonlinearity is thermal, and the magnitude and sign of the nonlinear refractive index are determined.     

Optical realization of bioinspired spiking neurons in the electron trapping material thin film

A thin film of electron-trapping material (ETM), when combined with suitable optical bistability, is considered as a medium for optical implementation of bioinspired neural nets. The optical mechanism of ETM under blue light and near-infrared exposure has the inherent ability at the material level to mimic the crucial components of the stylized Hodgkin-Huxley model of biological neurons. Combining this unique property with the high-resolution capability of ETM, a dense network of bioinspired neurons can be realized in a thin film of this infrared stimulable storage phosphor. When combined with suitable optical bistability and optical interconnectivity, it has the potential of producing an artificial nonlinear excitable medium analog to cortical tissue.     

激光共聚焦生物芯片扫描仪的光学特性

生物芯片扫描仪是生物芯片能否得到广泛应用的关键仪器，在分析了激光共聚焦生物芯片扫描仪的成像特性的基础上，详细地论述了生物芯片扫描仪的光强分布函数，光学信息量等光学特性，从而得出生物芯片扫描仪的高分辨力特性，为研制高精度，高分辨力的生物芯片扫描仪打下了坚实的理论基础。