氯化钠晶体色心近红外光谱精细结构

在９～７７Ｋ温度范围内，在γ射线辐照和Ｈｅ＾＋注入的氯化钠晶体中观测到Ｒ２和Ｎ１心零声子线，以及其它窄吸收线，并在不同温度下系统地测量了这些吸收线的光谱特性和热稳定性。     

LiF:OH单晶的光谱特性

本文报道了用OH基因掺到氟化锂晶体里,提高色心的热和光的稳定性的机理.同时,我们还在单晶LiF:OH赋色处理过程中生成的过氧离子(0_2~-)中观察到放大的自发辐射,它是一串零声子线的辐射.     

LiF晶体色心超辐射的实验研究

在众多的碱卤色心晶体中,LiF晶体色心的光热稳定性是较高的,其室温F_2色心和F_3~+色心激光运转已实现。F_2色心和F_3~+色心吸收带高度重迭,形成了一个单峰的吸收带(室温下测量),用单一波长泵浦,在同一块晶体中实现了F_3~+色心和F_2色心激光运转。文献[4]报道了所观测到的LiF晶体F_3~+色心放大的自发辐射现象,对F_3~+色心的光学增益系数进行了相应的测量。本文中,对LiF晶体F_3~+色心和F_2色心超辐射现象作了进一步的实验研究。     

YGG:Cr~(3+)晶体的光谱特性研究

本文通过实验研究了YGG:Cr~(3+)晶体的光谱特性。报道了室温下的吸收谱;10K、133K、300K的荧光谱;以及荧光寿命,无辐射跃迁几率,辐射量子效率与温度之间的依赖关系。从吸收谱及荧光谱中确定在C_(31)(S_6)低对称场微扰下,Cr~(3+)离子在基质YGG中2T_1能级分裂的子能级及基态~4A_2←→~2E零声子跃迁R线的位置。     

掺杂氟化钠晶体色心的零声子跃迁和光谱烧孔

在10～77K测量温度范围内,从室温伽马辐照着色的掺羟NaF晶体中观察到R2和N^-带零声子线(ZPLs)。用普通分光光度计的光在10K下能将N^- ZPLs完全漂白。用其更窄带的光在10K能在此线的吸收光谱上烧出1个明显的孔。在适当温度下,用紫外光照射能将此线的光漂白几乎全都恢复。在不同温度下,研究了未掺杂NaF晶体821nmZPL光谱特性随温度的变化关系,并估算出对应的Huang-Rhys因子约为2．49。     

氯化钠晶体注入着色

用自制的电注入装置,对氯化钠（NaCl）晶体进行电注入并使之有效着色,在晶体中产生F色心、胶体（C）心和一些未知色心。采用3种不同条件对NaCl晶体进行电注入,详细研究了温度和电压对色心浓度的影响。研究结果表明,随着温度和电压的升高,色心的浓度增大,并且存晶体不同部位,相应色心浓度不同。     

氟化锂晶体F3^＋色心四波混频研究

利用简并四波混频技术观测到LiF晶体中F_3~+色心的非线性光学相位共轭效应,以脉冲染料激光为泵浦光得到最大相位共轭反射率约为0.1%,根据LiF晶体F_3~+色心的能级特点从理论上阐明了F_3~+色心系统非线性饱和吸收和四波混频的物理起源。     

用于紫翠宝石激光器调Q的色心晶体

色心晶体做为被动激光Q开关元件较染料开关有显著的优点:激光束畸变小、破坏阈值高和可在高重复频率条件下工作等。积极探索不同种类的色心调Q晶体适应不同波长激光器是很有意义的。对宽带可调谐紫翠宝石激光器来说,色心晶体有与之匹配的宽吸收带,可在整个调谐区内实现调Q,其优点更为突出。 紫翠宝石(BeAl_2Q_4:Cr~(3+))激光器是室温下运转的终端声子激光器,调谐范围在700～800nm之间,发射中心波长在750nm附近,和棒内温度有关。根据波长匹配原则——激光发射波长和色心吸收带峰相重合,我们选择了两种色心晶体对其进行调Q。一为LiF:F_3~-色心晶体,一为NaF:F_2~+色心晶体。二种基质材料在上述激光波长上的吸收均很小。利用     

YGG:Cr~(3+)晶体光谱特性的研究

实验测定了YGG:Cr~(3+)晶体室温下的吸收谱,结合133K、300K下的荧光谱确定了~4A_2→~2T_1跃迁的精细结构和~4A_2→~2E零声子跃迁R线(R_1,R_2)的位置。采用激光诱导荧光法(LIF)给出了10K、133K、300K下的荧光谱,并给出了荧光寿命、无辐射跃迁几率以及辐射量子效率与温度之间的依赖关系曲线和实验值。从室温吸收谱和荧光谱中确定了在C_(3i)(S_6)低对称场微扰下~2T_1的分裂子能级并与多重散射x_a方法(M_s—x_a)计算的结果进行了比较,理     

电清洗人造石英晶体技术的研究

该文采用电清洗技术研制出高稳定性,高可靠性,低腐蚀隧道密度的人造石英晶体.通过对电清洗工艺技术的研究,可将腐蚀隧道密度≤100条/cm2、Na+质量分数为2.33×10-6的石英晶体腐蚀隧道密度降低到≤10条/cm2,Na+质量分数减少到0.3×10-6.采用电清洗石英晶体技术研制出了腐蚀隧道密度≤3条/cm2,抗辐射性能提高2个数量级.     

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.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

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.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

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.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

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.