掩埋隧道结VCSEL芯片小信号等效电路模型

提出了适用于一种1.55μm掩埋隧道结垂直腔面发射激光器(VCSEL)芯片的小信号等效电路模型.等效电路的提出是基于半导体激光器速率方程以及VCSEL芯片结构,电路中各元件都有严格的物理意义.根据实验测得芯片的反射系数及传输参数,通过小信号等效电路仿真模拟,得到电路各元件参数值.不同偏置电流下,模拟结果与实验结果吻合都非常好,证明了该等效电路的有效性.     

单模半导体激光器等效电路模型

介绍了单模半导体激光器的大信号、小信号及噪声等效电路模型，给出了确定模型参数的一般方法，并在ＰＳＰＩＣＥ中以电路宏模型的方式实现了激光器的大信号模型，对激光器小信号调频响应和大信号非线性失真特性进行了计算机时域模拟。     

光探测器芯片小信号等效电路模型的建立

提出了一种光探测器芯片小信号等效电路模型及其建立方法.首先根据光探测器的物理结构确定其等效电路模型,模型考虑了影响光探测器高频性能的主要因素.然后精确测量了光探测器芯片的S参数,通过遗传算法对测量的S参数进行拟合,最终计算出模型的各个参量.在130MHz～20GHz范围内的实验结果表明,模型仿真结果与测量结果相吻合,证明了建模方法的可靠性.该模型有效地模拟了光探测器芯片的高频特性,利用该模型可以对光探测器及相应光电集成器件进行电路级仿真和优化.     

单模半导体激光器等效电路模型

介绍了单模半导体激光器的大信号、小信号及噪声等效电路模型，给出了确定模型参数的一般方法，并在ＰＳＰＩＣＥ中以电路宏模型的方式实现了激光器的大信号模型，对激光器小信号调频响应和大信号非线性失真特性进行了计算机时域模拟。     

一个简单的量子阱激光器等效电路模型

给出一个新的量子阱激光器等效电路模型,由量子阱激光器单模速率方程推导得到并在电路模拟程序ＳＰＩＣＥ中完成。该模型考虑了热辐射效应和分离限制区域（ＳＣＨ）内的载流子工作情况,给出了新的光增益表达式。并利用该模型对单量子阱激光器的小信号特性和瞬态大信号特性进行了预测,模拟结果表明和速率方程的直接求解结果吻合很好。     

基于速率方程的垂直腔表面发射半导体激光器温度模型与仿真

建立了一个基于速率方程、考虑了热效应、可以模拟非直流 (即小信号和瞬态调制下 )特性 ,且适用于通用电路仿真器的垂直腔表面发射半导体激光器 (VCSEL)的简单等效电路模型。并通过PSPICE仿真结果与实验对比验证了模型的适用性     

光探测器芯片小信号等效电路模型的建立

提出了一种光探测器芯片小信号等效电路模型及其建立方法,首先根据光探测器的物理结构确定其等效电路模型,模型考虑了影响光探测器高频性能的主要因素，然后精确测量了光探测器芯片的S参数,通过遗传算法对测量的S参数进行拟合,最终计算出模型的各个参量，在130MHz-20GHz范围内的实验结果表明,模型仿真结果与测量结果相吻合,证明了建模方法的可靠性。该模型有效地模拟了光探测器芯片的高频特性,利用该模型可以对光探测器及相应光电集成器件进行电路级仿真和优化。     

内腔接触氧化限制型垂直腔面发射激光器小信号调制特性研究

建立了一种适用于多量子阱垂直腔面发射激光器(VCSEL)的多层速率方程模型.在理论与实验基础上,对器件进行小信号分析,得到了光子密度、载流子俘获、逃逸和隧穿时间等关键参数对VCSEL频率响应特性的影响.结果表明VCSEL调制带宽会随着输出功率增大而变宽.并进一步研究了内腔接触氧化限制型VCSEL的寄生电参数及其寄生电路,对其小信号频率响应进行了模拟分析.     

垂直腔表面发射激光器的小信号等效电路模型的研究

结合分析法和优化法,在ADS软件中对垂直腔体表面发射激光器(VCSEL)的小信号模型进行模型参数的提取,给出了具体的计算公式、参数提取数值及不同偏置电流下模拟结果和测量结果之间的误差,可以清楚的看出,这种提取参数的方法是十分高效的,可以使模拟结果和测量结果之间的误差相对于用单一的分析法提取出来的误差更小.     

垂直腔面发射激光器的小信号电路模型和调制特性

给出了垂直腔面发射激光器的小信号电路模型和调制特性,调制特性用解析计算和电路模型模拟两种方法得到,解析计算和电路模型模拟的结果一致,实验证实了电路模型的正确性.     

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.     

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.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks