WDM用增益平坦的高增益低噪声双段级联掺铒光纤放大器

给出了设计波分复用(WDM)用高增益、低噪声和宽带宽增益平坦的双段级联掺铒光纤放大器(EDFA)的一般步骤和方法.通过优化设计各种参量,研制出了一台高增益、低噪声和宽带宽增益平坦的双段级联EDFA样机,实现了从1524.8～1561.4 nm共36.6 nm带宽内±0.325 dB的平坦增益,0 dBm输入时,饱和输出功率大于15 dBm的高功率输出;噪声指数低于5 dB.     

High extinction ratio multiplexer/demultiplexer with a Mach-Zehnder interferometer and a fiber loop mirror

A novel structure of high extinction ratio multiplexer/demultiplexer with a Mach-Zehnder interferometer (MZI) and a fiber loop mirror (FLM) is proposed. The experimental results show that the extinction ratio can be enhanced about two times in comparison with the conventional MZI.     

镜面起伏对1.55μm Si基MEMS光滤波器的影响

用传输矩阵方法,在简化的光学模型基础上,分别讨论了分布式Bragg反射镜DBR(Distributed Bragg Reflector)的生长精度及镜面起伏对1.55 μm Si基MEMS(Micro-Electro-Mechanical-System)可调谐光滤波器透射谱的影响.计算表明:DBR生长误差仅使主透射峰位置发生变化,而镜面起伏是导致主透射峰性能劣化的主要原因,它使得FWHM增大,透射峰强度下降.理论计算结果能较好地解释实验现像.在此基础上,进一步讨论了引起镜面起伏的多种原因,并提出了可能的解决方法.     

一类四阶两点边值问题的可解性

本文考虑如下四阶完全拟线性两点过值问题：y（4）＝f（x，y，y′，y″，y），y（0）＝y″（0）＝y′（1）＝y（1）＝0，给出了不限制f增长的可解性条件。     

通过外加应变于高双折射环镜实现掺铒光纤激光器的输出功率控制

本文提出一种基于外加应力于高双折射环镜的输出功率可调控的掺铒光纤激光器新颖结构。通过将高双折射光纤环镜中的部分双折射光纤粘贴于一个等强度梁的中性面上，在梁尾端作用不同的应力，由于双折射光纤的长度和双折射的改变可使环镜的反射率从0.8%变化到100%。以该环镜作为线形腔光纤激光器的输出腔镜，实现了动态范围达33dB的输出功率可调控的掺铒光纤激光器。该激光器不仅具有结构简单、成本低廉的优点，而且利用该机理可以很容易的找出最优腔镜反射率，从而使线形腔光纤激光器的输出性能实现最优化。     

近物所量子多体动力学实验研究反应谱仪

介绍利用反应显微成像谱仪实验研究高电荷态离子与原子分子碰撞动力学的技术,讨论了实验测量反应末态全部离子和电子动量矢量,得到反应末态动量空间的全部信息,从而反演碰撞反应动力学过程的路线.描述了在近物所开展量子多体动力学实验研究的计划.     

Fibre Bragg Gratings Inscribed in Homemade Microstructured Fibres

Fibre Bragg gratings （FBGs） are inscribed in homemade microstructured fibres by the standard phase mask method. Enhanced couplings between the forward fundamental mode and backward cladding modes are obtained. The mode coupling and spectral characteristics are investigated experimentally. The cladding mode resonances can be affected by filling active materials into the air holes, which will be useful for the implementation of tunable photonic devices in optical fibre communication and sensing systems.     

Properties of All-Solid Square-Lattice Photonic Bandgap Fibres

Properties of all-solid square-lattice photonic bandgap fibres are studied for the first time to the best of our knowledge. Using the plane-wave expansion method and finite element method, we investigate the mode, effective area, confinement loss and dispersion of such fibres. The simulation results demonstrate that the proposed effective mode area of all-solid square-lattice photonic bandgap fibres is 1.25 times larger than triangular-lattice ones and the confinement loss of the fibres is no more than 0.1 dB/m within the bandgap.