激光对卫星的威胁及其防护

激光技术的广泛应用,由此带来的激光损伤和激光威胁日益严重.在现代高技术战争中,卫星的作用越来越重要,而激光反卫星武器的出现和发展,使卫星也面临着激光的威胁,因此,对卫星的激光防护材料和防护措施的研究具有重要的意义.介绍了激光反卫星武器的分类、性能、作用方式和关键技术;探讨了激光武器对星载光电传感器和材料的杀伤机理;总结了目前基于线性光学原理、非线性光学原理和相变光学原理的激光防护材料的性能、优缺点和改进措施,其中详细介绍了比较有发展潜力的富勒烯、卟啉和VO2薄膜激光防护材料;介绍了几种卫星结构材料的激光防护措施.这有助于对卫星的激光防护的重要性和技术手段的进一步认识.     

高能激光武器的发展及卫星激光防护膜的研究

现代战争中激光武器具有举足轻重的作用，激光武器对卫星实施的致盲攻击使抗激光损伤膜的研究成为关键。介绍了高能激光武器的种类及卫星防护膜的研究现状，总结了几种防护措施的优缺点，指出了卫星防护膜的发展趋势。     

激光反导与导弹反激光措施综述

简要介绍了激光武器与对抗导弹研究近况,对导弹反激光措施进行了综述,包括旋转导弹、超高音速导弹、反光涂层/隔热护层等加固结构/材料,以及光电器件的防护.指出反激光措施将有助于提高导弹的生存能力与突防能力,并提出"强化辐照,加速损伤"将是强激光武器对抗导弹反激光措施的一个重要研究内容.     

美国高能激光武器的发展及其面临的挑战(下篇)

首先介绍了美国高能激光武器的发展战略和高层技术路线(上篇)。然后分别评述了近一年来机载战区激光武器,战术高能激光武器和机载战术激光武器,天基激光武器,地基激光反卫星武器和舰载激光武器取得的重大进展,分析和讨论了它们面临的技术挑战和可能采取的对策(下篇)。     

美国高能激光武器的发展战略(上篇)

首先介绍了美国高能激光武器的发展战略和高层技术路线(上篇)。然后分别评述了近一年来机载战区激光武器、战术高能激光武器和机载战术激光武器、天基激光武器、地基激光反卫星武器和舰载激光武器取得的重大进展,分析和讨论了它们面临的技术挑战和可能采取的对策(下篇)。     

浅析激光对抗的“攻”与“防”

论述了激光对抗的两个方面,即“攻“与“防“。在进攻部分中介绍了几种激光进攻手段,如激光测距、激光制导、激光雷达及激光武器等,说明现代战场上的激光威胁和进行激光对抗的必要性;在防御部分中有针对性地阐述了各种激光对抗措施以及防护方法,如激光告警、激光干扰、激光反干扰及简单防护措施。最后对激光对抗的发展趋势作了概述。     

飞航导弹抗激光武器攻击的防护技术

激光武器以激光束直接干扰、致盲乃至完全破坏各种武器装备中的光电装置甚至摧毁武器本身.论述了激光武器的分类及激光武器的软、硬杀伤,在此基础上从反侦察、抗激光欢杀伤以及抗激光硬杀伤等多个方面研究了飞航导弹武器的防护技术.     

强激光武器辐照弹道导弹温度场数值模拟

强激光武器的出现和投入实战对弹道导弹的生存造成了严峻的威胁。根据激光武器的特性和作战机理,分析了导弹壳体上激光辐照强度的影响因素,得到了导弹壳体上激光辐照强度的计算公式,从而计算出了不同作战距离下的激光辐照强度和光斑半径;建立了机载激光武器(ABL)照射弹道导弹壳体的有限元模型,得到了不同作战距离下弹道导弹被打击后内外壁面的温度分布以及内外壁面温度随时间的变化曲线。以上计算模型及计算结果为激光武器对弹道导弹的毁伤效应分析和激光防护方面的研究提供重要参考。     

非线性高能激光防护材料研究进展

高能激光武器对军事目标的生存构成严重威胁,开展高能激光防护技术研究显得尤为重要。在分析高能激光防护材料基本工作原理的基础上,分别对基于三阶非线性效应、热致相变效应和多种效应复合的三类典型高能激光防护材料的防护原理及其研究进展进行了阐述,并对非线性高能激光防护材料的发展趋势进行了展望。     

卫星多功能激光防护膜层的研究

卫星在现代战争中具有突出的制空作用，而激光武器能对其实施致盲打击，因此抗激光损伤膜已成为了关键技术之一。本文主要介绍了抗激光损伤的评价参数和卫星激光防护膜的发展现状，总结目前存在的技术问题，最后提出将有机非线性光学材科和热致相变材料复合，利用其各自的优点，有望制备出新型的卫星防护膜。     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

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.     

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.     

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.     

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.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

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.