宽带集成光波导放大器的结构设计

对带薄膜滤波器宽带集成光波导放大器的结构进行了设计,并对单程、双程与多程三种放大器结构加以比较,单程结构的特点是结构简单、制作方便,不足之处是增益不高;双程结构特点是器件的整体增益较高但制作不方便,将两者优点结合得到多程波导放大器结构,分析表明多程宽带集成光波导放大器结构是一种较理想的结构。

Cu^(2+)离子注入的石英光波导的特性研究（英文）

利用Cu^(2+)离子注入的方式在熔融石英和石英晶体上分别制备了平面光波导结构.通过棱镜耦合实验测试了两种光波导的导模特性,结果表明:在同样的注入条件下熔融石英上形成了增加型的光波导结构,而石英晶体上形成了位垒型的光波导结构.研究了退火温度对两种光波导导模折射率的影响,熔融石英光波导中导模的折射率随着退火温度的升高而降低,而石英晶体光波导中导模的折射率随着退火温度的升高先增加后降低.为了进一步分析离子注入两种材料形成光波导的微观机理,利用SRIM模拟了Cu^(2+)离子注入两种材料的电子能量损失和核能量损失,并且模拟了两种光波导结构的折射率分布.模拟结果表明:熔融石英光波导的主要形成原因是离子注入表面的折射率大于其体材料的折射率,而石英晶体光波导的主要形成原因是离子射程末端的折射率小于其体材料的折射率.因此,在熔融石英光波导的形成中电子能量损失起主要作用,而在石英晶体光波导的形成中核能量损失起主要作用.

光波导参数测试

T N252 99055160GeSi/Si多量子阱光波导模特性分析和吸收层结构设计=Analysis and optimum design on GeSi/SiMQW optical waveguide and absorbtion laver[刊,中]/李娜,李宁,陆卫,沈学础(中科院上海技物所红外物理国家实验室.上海(200083)),李国正,刘恩科(西安交通大学电子工程系.陕西,西安(710049))//红—外与毫米波学报. 1998,17(3).—203—208根据普适于任意阱数的方波折射率分布的多量子阱光波导的模场分布函数和模特征方程,分析了在以GeSi/Si多量子阱为波导芯、Si为覆盖层的光波导结构中,Ge含量、周期数、占空度、厚度、折射率分布等参量对光波导传播常数的影响,并结合吸收特点对MQW吸收层结构进行优化设计。图6表1参6(方舟)TN252 990531612D—FDTD法计算波导截止频率的激励源设计=Designof excitation source in computing cut—offfrequencies of waveguides by

多孔硅制备及在太阳能电池中的应用研究进展

多孔硅是通过对单晶硅片进行电化学腐蚀或适当的化学腐蚀而形成的一种纳米结构半导体材料。多孔硅纳米材料因其巨大的表面积、可调谐的光学性质和良好的相容性,被广泛应用于电子器件、生物传感、化学传感、药物传递、生物芯片等诸多领域。当前研究的挑战主要在于开发更简单高效的多孔硅纳米材料合成方法以及提高其在实际应用中的表现。综述了多孔硅纳米材料的制备方法及其光致发光在太阳能电池领域中的应用。

通信工程中光纤技术的应用及设计分析

随着科技的快速发展,通信工程领域发生了巨大的变化。其中,光纤通信技术作为一种高速传输媒介已经得到了广泛应用,也成为通信工程领域的研究重点。旨在探究光纤技术在通信工程中的应用和设计分析。通过分析光纤通信系统的基本原理和传感技术,本文从系统设计的角度出发,探究了光纤通信系统在不同场景中的应用及其优势,为通信工程中光纤技术的发展提供理论支持和实践指导。

试析包装特种光泽印刷

近年来,消费者已不再把包装仅当作保护商品的躯壳,开始增加了对美的需求.而使消费者挑剔的目光被一些金碧辉煌、温文尔雅、变幻莫测、珠光宝器光泽的高档次印刷包装所吸引和陶醉,并激发起商品购买欲的,就是特种光泽印刷.

Structure optimization of polymeric Mach-Zehnder rib waveguide

A systematic analysis of the polymeric Mach-Zehnder rib waveguide is presented based on the calculation and optimization. The simulation is carried out with the Effective Index Method (EIM) and two-dimensional (2-D) Finite Difference Beam Propagation Method (FD-BPM). The large refractive index step between the consecutive polymer layers is reduced by using EIM and thus the precision of the calculation is ensured. The important param- eters of the waveguide such as Y-junction angle and the separation gap are discussed and their relationships with the optical power propagation and the loss characteristics are investigated in this paper. The total loss of the opti- mized structure is 0.258 dB.

STUDY ON RECTANGULAR WAVEGUIDE GRATING SLOW-WAVE STRUCTURE WITH COSINE-SHAPED GROOVES

This paper focuses on a new rectangular waveguide grating Slow-Wave Structure (SWS) with cosine-shaped grooves and studies the propagation characteristics of the wave in the SWS. By using the approximate field-matching conditions,the dispersion equation and the coupling impedance of this circuit are obtained. The dispersion curves and coupling impedances of the fundamental wave are calculated and the influences of the various geometrical dimensions are discussed. The results show that the bandwidth of the cosine-shaped groove SWS is much wider than that of rectangular-shaped groove one. And reducing the groove width can broaden the frequency-band and decrease the phase-velocity,while increment of the groove-depth can also decrease phase-velocity. For above cases,the coupling impedance is more than 16Ω. The present analysis will be helpful on further study and design of the RF systems used in millimeter wave Traveling Wave Tube (TWT).

The development of studying flexible pipe bend reinforced by Kevlar fibers

The flexible pipe bend can not only reduce the structural vibration and fluid noise in pipeline, but also realize the flexible connection of a horizontal line and a vertical line and compensate the displacement of three dimensions produced by the shock or vibration of pipeline in the special situations. Up to now, little attention has been paid to study the flexible pipe bend applied in the pipeline of medium or high pressure, because no appropriate framework materials can be used to reinforce it which must endure the burst pressure higher than 10 MPa. The investigation shows that it is possible to produce the flexible pipe bend of medium or high pressure if such fibers with high performance as Kevlar fibers are used to be its reinforced materials. However, its structural designing theory, manufacturing technology and measuring techniques aren't yet perfect and systematic, which leads to the instability of the performance of products. Furthermore, few references about its research can be seen. Therefore, it is necessary to systematically and thoroughly develop the structural designing theory, manufacture technology and measuring techniques of flexible pipe bend.

上海硅酸盐所在平面波导激光陶瓷研究中取得系列重要进展

集成光学中的光波导结构对激光增益介质的几何形状设计是一种启示。波导结构是介质衬底表面上或内部形成的折射率相对较高的微型区域,这一区域被折射率较低的区域包裹,从而能将光限制在微米量级的结构内进行传输。将光波导结构应用于激光增益介质,其最大特点是它能够有效地限制光束发散,提高增益介质中的光密度,从而实现低阈值、高效率、高功率的激光输出。同时,

集成光学、波导理论

TN252 2001031907光纤-手征光纤耦合光波导偏振响应特性的实验研究=Experimental investigation on polarizationresponse of composite light waveguides couplingvia fiber and chiral fiber[刊,中]/陶卫东,董建峰,白贵儒,张玲芬(宁波大学光纤通信所.浙江,宁波(315211))∥光学技术.-2000,26(6).-517-518研究了在光波段内对手征波导的偏振响应特性。在已研制出的D形微孔光纤中注入手征液体,形成光纤-

集成光学、波导理论

TN252 2003010453幂次率非线性包层平板波导传播特性的无量纲表示=Scaling rules for slab waveguides with power law nonlinearcladding[刊,中]/陈伟亮(北京交通大学物理系.北京(100044)),佘守宪…//光电子·激光.-2002,13(5).-496-500采用无量纲参数表示法,分析了芯区为线性、包层和衬底为幂次率非线性材料的NLN型非线性平板光波导结构的传播特性,得到了普适的计算公式和曲线族。图6参7(于晓光)

集成光学 集成光学、波导理论

TN25 2005010333 集成光学国际研究进展=Development of international integrated optics[刊,中]／张彤(东南大学电子工程系.江苏, 南京(210096)),崔一平∥电子器件．-2004,27(1).- 196-201 介绍了集成光学基本概念及其主要应用领域,分析了集成光学国际研究现状。在理论研究方面,对新型器件的设计、计算和模拟以及基于固体物理学和波动光学的基础理论研究是目前研究热点;而在器件研究方面。

Experimental Research on Erbium-doped Superfluorescent Fiber Source

The effects of the variations in fiber length,fiber mirror reflectance on efficiency and output power are experimentally investigated for erbium-doped double pass backward superfluorescent fiber sources (SFSs).The influence of fiber length on mean wavelength stability (MWS) has also been demonstrated.By incorporating a short section of un-pumped erbium-doped fiber (EDF) at the output port,the pump power dependent on MWS becomes independent of pumped EDF length.This is a novel phenomenon that hasn’t been reported up to now,and should be helpful to SFS fabrication and theory analysis.By using a fiber Michelson interferometer as spectrum slicing component,a multi-wavelength fiber source (MWFS) with ～20 channels (from 1 542 nm to 1 559 nm) is got.The MWFS has a channel spacing of ～0.8 nm which satisfies ITU-standard.The intensity fluctuation among channels is less than 0.5 dB,and the extinction ratio of all channels is above 14 dB.This kind of MWFS should be useful to wavelength division multiplexing systems.

Diode-pumped Nd:YAG/LBO CW yellow laser at 588.9 nm

A design of diode-pumped Nd.YAG laser with a single crystal that generates simultaneous laser action at the wavelengths of 1064 nm and 1319 nm was presented and continuous-wave （CW） of 588.9 nm was obtained for the first time by use of type-I critical phase-matching LBO crystal intracavity sumfrequency mixing. The maximum output power of 62 mW is achieved with an incident pump power of 1.8 W. The optical-to-optical conversion efficiency is up to 3.4% ,and the power instability in 24 h is better than ± 2.7 %.

上海硅酸盐所在平面波导激光陶瓷研究中取得系列进展

集成光学中的光波导结构,对激光增益介质的几何形状设计是一种启示。波导结构是介质衬底表面上或内部形成的折射率相对较高的微型区域,这一区域被折射率较低的区域包裹,从而能将光限制在微米量级的结构内进行传输。将光波导结构应用于激光增益介质,其最大特点是它能够有效地限制光束发散,

Propagation property of electromagnetic waves in fractal cantor photonic crystals

Two novel structures of fractal Cantor multilayer with defects are presented. The Optical transmission matrix method is used to calculate the transmittance and the reflectance. Compared with the general Cantor multilayer, these novel structures have wider stopbands and show super narrow bands in the middle of the wider stopbands, which can be used as super narrow bandpass filters. The pass band can be less than 0.6 nm near the infrared wavelength of 1530 nm when there is an embedded defect in the cantor multilayer. The optical transmission in the central wavelength is higher than 99 %, which means a very low insert loss. If there are three layers, three super narrow peaks can be found in the middle of the stopband. The central wavelengths are respectively 1232.4 nm, 1372.8 nm and 1538.3 nm. It is much better than other kinds of narrow band filters and it may be used in the optical communications.

Characteristics of long period microtremor and validation of microtremor array measurements in inland areas of China

To study the characteristics of long period microtremor and applicability of microtremor survey,we have made microtremor observations using long period seismometers of the China's mainland from coastal cities like Shanghai and Tianjin through Beijing,Xi'an,to the far inland cities of Lanzhou and Tianshui.The observation shows that the level of power spectrum of long period microtremors reduced rapidly from the coast to the inland area.However,the energy of long period microtremors in Beijing,Xi'an,Lanzhou and Tianshui area are only approximately ten-thousandth to thousandth of that in Shanghai.Aiming at the complexity of the underground structure in the far inland,a series of underground structure models with different distributions were assessed using three-dimensional,dynamic finite element method(FEM) analyses.The results were used to evaluate microtremor survey methods and their limitations with regard to aggregate variability and thickness determinations.Multiple-wave reflections between layers with the change of underground structure distribution occurred,which have significant effect on the performance of the different field approaches.Information over a broad spectrum from which velocity-depth profiles were produced via inversion approaches.Neither the thickness nor the shear waveVelocity V of the subsurface layer inversion results appeared over a large evaluation with increasing slope angle.In particular,when the angle of the model reached 45°,it could not be accurately evaluated using one-dimensional inversion methods.Finally,the array microtremor survey(AMS) was carried out in Shanghai City,China.Although AMS techniques do not have the layer sensitivity or accuracy(velocity and layer thickness) of borehole techniques,the obtained shear wave velocity structure is especially useful for earthquake disaster prevention and seismic analysis.

High-Dimensional Nonlinear Envelope Equations and Nonlinear Localized Excitations in Photonic Crystals

We investigate the nonlinear localized structures of optical pulses propagating in a one-dimensional photonic crystal with a quadratic nonlinearity. Using a method of multiple scales we show that the nonlinear evolution of a wave packet, formed by the superposition of short-wavelength excitations, and long-wavelength mean fields, generated by the self-interaction of the wave packet, are governed by a set of coupled high-dimenslonal nonlinear envelope equations, which can be reduced to Davey-Stewartson equations and thus support dromionlike high-dimensional nonlinear excitations in the system.