双层YIG波导中静磁体波的传播特性

本文研究了在倾斜静磁场作用下,双层YIG薄膜波导结构中静磁体波的传播特性,得到了其色散的特征方程,计算了磁场倾角从5°到20°范围内双层波导结构中静磁体波传播的色散关系和延迟特性.结果表明,斜向场情况下在双层YIG薄膜结构中传播的静磁体波适合应用于高频范围,并且通过调节磁场倾角可以获得比单层膜波导结构更好的延迟率可调范围.斜向场情况下采用双层YIG薄膜结构,对于改进静磁波器件和磁光波导器件的性能具有十分重要的意义.     

微波单晶铁氧体器件再展雄风

本文叙述了微波单晶铁氧体器件——YIG调谐滤波器(YTF);YIG调谐振荡器(YTO);YIG调谐器件组件;YIG单晶薄膜及平面器件;磁光器件的概况及其发展方向。 微波单晶铁氧体器件已有近50年发展历史。YIG调谐滤波器(YTF),YIG调谐振荡器(YTO)是其典型产品,产品已经系列化。频率范围从0.5～40GHz,有点频、     

用于光通信的新型磁光Bragg器件的优化分析

采用变分法研究了横向不均匀偏置磁场作用下掺Bi的YIG薄膜中微波静磁波对导波光的Bragg衍射效率,理论计算得到的衍射效率曲线与实验结果基本一致.计算表明,采用适当的不均匀偏置磁场、在一定范围内增大激发电流以及优化波导结构等方法可有效提高磁光Bragg器件的衍射性能;减小Bi:YIG薄膜厚度也可提高导波光衍射效率,但磁光带宽有所减小.     

多层窄样品中静磁表面波宽度模的色散特性研究

本文建立了具有任意参数多层薄膜结构的窄样品中静磁表面波宽度模的普遍色散关系,适用于利用多层薄膜控制静磁表面波色散特性的所有情况.对两周期 多层膜结构窄样品中静磁表面波宽度模的色散特性进行了数值计算,得到了多层膜中的高阶宽度模式,多层薄膜结构的参数可以有效地控制静磁表面波的色散特性,样品宽度效应对色散也有明显的影响.根据数值计算结果对不同宽度的YIG薄膜样品在4.2~5.2GHz的频率范围进行实验,实验测试结果与理论分析相吻合.     

可调谐非色散延迟线

使用表面磁导率法得到斜向磁化金属/电介质/钇铁石榴石(YIG)/钆镓石榴石(GGG)/金属多层电介质结构中静磁波的传播方程.通过分析静磁正向体波(MSFVW)和静磁反向体波(MSBVW)延迟特性设计出级联MSFVW-MSBVW延迟线系统,该系统通过调节MSBVW延迟线激发场角起到控制非色散延迟时间的作用.数值计算得到一个近500MHz的非色散延迟带宽,延迟时间具有156.4～186.6ns/cm的可调范围.     

静磁波器件

一、引言基于外延钇铁石榴石(YIG)的静磁波(MSW)器件可用于微波信号频率或宽带微波中频的信号处理。由于静磁波器件在微波频率的传播损耗低于30分贝/微秒,以及它们的平面几何形状使这种器件颇具吸引力,并且,约     

单相LCL型光伏逆变器新型控制方法研究

传统的三阶LCL滤波器存在谐振尖峰问题,文中基于LCL滤波器提出外环使用准比例谐振和改进型重复器为核心的控制系统,内环使用陷波器无源阻尼法。QPR可以实现无静差跟踪,改进重复控制有良好的高次谐波抑制能力,陷波器无源阻尼消除滤波器谐振问题。通过对实验样机仿真与实验,结果表明提高了系统的动态性能和稳定性。     

静磁前向体波(MSFVW)信道接收器的研究

静磁前向体波(MSFVW)要求外加直流偏置磁场和静磁波波导YIG膜平面相垂,因而极易安排直流磁路和微波电路。把一个MSFVW阵列置于一个线性渐变外磁场中,每个滤波器中心频率不同,形成一个信道接收器,可完成不同频率信号的实时分离。本文从理论和实验说明这种器件的特性,并指出器件实用化尚需进行的工作。     

静磁正向体波与导波光的非共线相互作用

在考虑静磁正向体波（MSFVW）传播损耗及微带换能器耦合损耗的情况下，利用耦合模理论推导出导波光（GOW）衍射效率的表达式，并针对掺铋钆铁石榴石（Bi-YIG)薄膜波导和钇铁石榴石（YIG）波导计算了GOW衍射效率的频率响应曲线。数值计算表明，虽然MSFVW在Bi-YIG薄膜中的传播损耗大于YIG薄膜，但前者具有很大的一级磁光系数，故Bi-YIG波导中GOW的衍射效率仍远大于YIG波导。     

微波固态振荡器的新进展

近二十年来,微波固态振蕩器是微波技术中最活跃、发展最迅速的领域之一。与微波电真空振荡器相比,它只需低电压电源,而且效率高、可靠性好、体积小,所以一直受到人们的重视。微波固态振荡器大体包含三个部分:(1)基本振荡源,用于产生高频振荡。它包括半导体有源器件、反馈网络;(2)调谐电路,用以决定频率。它可以是微波谐振腔,也可以是釔铁柘榴石YIG单晶球、介质谐振器等;(3)输出匹配网络,使能量有效地输出。新型的声表面波(SAW)及静磁表面波(MSSW)振荡器中的声及磁波延迟线则可同时起反馈和调谐的作用。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.