导波法测量吸收薄膜的复介电系数和厚度

具有吸收特性的波导薄膜,其衰减全反射（ＡＴＲ）峰的位置和形状包含了薄膜诸多特征多数的信息,在同时考虑棱镜的耦合和材料的吸收的基础上,本文用一阶微扰理论推导了微扰传播常数的解析公式,并且介绍了通过分析薄膜的衰减全反射峰来计算吸收薄膜的复介电系数和厚度的方法。     

一个有趣的力学实验

介绍一种由矿泉水瓶制作奇异转动的力学实验, 用两个互相垂直的简谐振动的合成来解释其转动的原理, 制作模型并进行验证, 得出木棒摩擦矿泉水瓶时, 瓶盖上的叶片同时参与了两个不同方向的振动, 这两个振动合成的结果使得瓶盖上的叶片发生转动的结论.     

Investigation of the influence of photobleaching process on the thermo-optic coefficient of disperse red 1/poly(methl methacrylate) film

The influence of photobleaching process on the thermo-optic coefficient (dn/dT) of disperse red 1/poly(methl methacrylate) film is investigated by using the attenuated total reflection technique. Experimental results show that the absolute values of the thermo-optic coefficient of fully bleached disperse red 1/poly(methl methacrylate) film are smaller than those of unbleached film. Moreover, the absolute value of anisotropy of the thermo-optic coefficient (dn_TE/dn_TM/dT) also decreases after the disperse red 1/poly(methl methacrylate) film that is fully bleached.     

衰减全反射型电压传感器的理论和实验研究

提出了一种新型反射型聚合物波导电压传感器理论,并且进行了实验研究。这种电压传感器采用棱镜波导耦合结构,在棱镜下底面依次镀有金属膜一聚合物一金属膜三层结构。通过两层金属膜对极化聚合物加电压,利用聚合物材料电光效应和导模共振吸收峰对聚合物折射率的敏感特性,通过反射光强的测量来确定作用电压的变化值。实验中的测试电压范围是从-140V至 140V,得到的线性度值为0．991,电压测量的分辨力为0．1V,电压测量灵敏度系数为0．0011V^-1。实验表明这种电压传感器具有良好的线性和较高的灵敏度。     

基于单通道反射型电光调制器实现不同路光同时调制的方法

提出了一种利用单通道反射型聚合物电光调制器同时调制不同路光的方法。衰减全反射结构的电光调制器,其每一个衰减全反射(ATR)峰的位置分别对应于一个导波共振模式。实验系统中利用衰减全反射导膜峰作为调制通道,使其每一路光路的入射角分别对应于不同导波共振模式的工作角,就可以实现利用单通道的电光调制器同时调制不同路光。提出了三种实现两路光同时调制的模式,并给出了三种模式的调制结果。结果表明,作为调制通道的导模阶数越低,调制效率越高。在832 nm光波波长下,采用最低阶导模进行调制时可以获得42.9%的调制效率。     

基于内反射效应的可变光学衰减器

提出一种基于内反射原理的可变光学衰减器，这种利用一加长的棱镜和涂于棱镜上下两底面的SiO2薄膜的简单结构，使随入射角变化的反射光实现弱偏振相关和大动态范围的衰减。     

Why SWKB approximation is exact for all SIPs

Using analytical transfer matrix (ATM) theory, the phase contribution devoted by the scattered subwaves is found to be independent of n and integrable for all known shape invariant potentials (SIPs) with translation. We also successfully explain why SWKB quantization condition yields exact bound-state spectra for all SIPs.     

Study on the normalized Laplacian of a penta-graphene with applications

Let L _n denote a linear pentagonal chain with 2n pentagons. The penta-graphene (penta-C), denoted by R _n is the graph obtained from L _n by identifying the opposite lateral edges in an ordered way, whereas the pentagonal Möbius ring is the graph obtained from the L _n by identifying the opposite lateral edges in a reversed way. In this paper, through the decomposition theorem of the normalized Laplacian characteristic polynomial and the relationship between its roots and the coefficients, an explicit closed-form formula of the multiplicative degree-Kirchhoff index (resp. Kemeny's constant, the number of spanning trees) of R _n is obtained. Furthermore, it is interesting to see that the multiplicative degree-Kirchhoff index of R _n is approximately of its Gutman index. Based on our obtained results, all the corresponding results are obtained for .     

集成电光器件电极的数值分析法

本文描述了一种数值分析方法,计算了集成光学中电光器件电极的电场分布。在电极无限薄的假设条件下,把数值分析法计算的结果同保角变换法的结果进行了比较,并讨论了电极厚度和缓冲层对电场以及特征参量的影响。计算结果表明电极厚度对电场分布影响较小,但特征阻抗和有效介电常数随电极厚度增加明显减小。而且使用缓冲层使波导的有效深度增加,电场强度减小,特征阻抗和有效介电常数都发生很大变化。利用这些特性可对集成光学电光器件的电极进行优化设计。     

Direct coupling of haloquinolines and sulfonyl chlorides leading to sulfonylated quinolines in water

A simple and efficient method has been developed for construction of sulfonylated quinolines via coupling of haloquinolines and sulfonyl chlorides in water. The present methodology provides an attractive approach to various sulfonylated quinolines in moderate to good yields with favorable functional group tolerance, which has the advantages of operation simplicity, readily available starting materials, excellent regioselectivity, scale-up synthesis, and organic solvent-free conditions.