空心新型光阱的实验研究

介绍了用锥镜法和取高级衍射光斑法来实现空心光阱的实验方法。用实验定性地证明了空心光阱轴向捕获力高于实心光阱。用图像分析法比较了空心光阱与实心光阱近中心横向光阱刚度 (光焦点附近小范围内的光阱横向刚性程度 ) ,表明同等条件下空心光阱的近中心横向光阱刚度弱于实心光阱。用流体力学法测量光阱的逃逸阱力随光功率的变化 ,表明同等条件下空心光阱的逃逸阱力大于实心光阱 ,因此空心光阱操纵微粒具有更高的稳定性。同时指出了空心光阱具有更低的热损伤 ,在低倍物镜下空心光阱具有更高的实用价值 ,以及空心光阱适于更加高精度的实验操作     

多种光声成像方法研究

阐述了光声成像的基本原理,综述了现有的几种光声成像方法、原理及成果。介绍了国内外多个研究小组在光声成像领域所取得的一些成果,主要包括:用超声探测器记录光声信号的滤波反投影算法光声成像;超声探测器结合声透镜的傅里叶方法;用探测光做载波调制光声信号,将光声信号转化为光信号,经光学系统解调,将样品像显示在CCD摄像机上的实时光声成像等。对比了几种光声成像方法,并提出了一些光声成像的新思路。     

半导体双稳态激光器在光注入下的实验研究

本文报道了InGaAsP/InP 双区共腔脊形波导双稳激光器在外光注入下产生光-光双稳特性及光-光放大的实验结果,给出了器件在直流及脉冲工作时的光-光双稳特性,并对结果进行了初步分析.     

低损耗聚合物互连光波导的制备及性能测试

对应用于宽带光互连的光印刷电路板(OPCB)制备技术进行了研究。作为光互连系统的传输介质,我们研究了互连光波导的性能。基于紫外光刻技术,在常规PCB基底上制备了聚合物光波导,研究了光波导的制备流程以及工艺参数;并且通过不断优化工艺参数,制备得到了低损耗的光波导;通过测试光波导的传输损耗以及眼图,分析了光波导的性能。光波导在850nm波长条件下的传输损耗可以达到0.13dB/cm,实现了10Gbit/s光通信信号的传输。     

基于MEMS的光开关技术研究

介绍了光开关、MEMS和MEMS光开关的基本概念.基于功能实现,重点分析了二维和三维MEMS光开关的实现机理与特性.针对两者不足,研究了一维MEMS光开关.分析了MEMS光开关的驱动方式,并针对静电驱动、二维MEMS光开关,研究了MEMS光开关控制系统.     

光限幅技术新进展

光限幅技术是基于非线性光学原理实现激光防护的技术。概述了光限幅基本原理,总结了光限幅技术的发展,比较分析各种光限幅效应与光限幅材料的优劣,介绍了光限幅材料新进展。     

LiNbO3：Fe,M（M=Mg^2＋,Zn^2＋,In^3＋,Sc^3＋）晶体中的信号光 …

分析了掺杂铌酸锂晶体的扇形噪声光的形成机制,讨论了信号光与扇形噪声光之间的光放大竞争问题,结果显示,由于信号光与扇形噪声之间光放大竞争,对于信号光的放大而言,存在一个最佳的光生伏特场,因而存在一个最佳入射泵浦光光强,使得信号光具有最大的放大倍数,同时噪声很弱。     

光有源器件中的光集成技术演变

从光集成技术在光有源器件中的应用与发展的角度出发,结合硅光平台、平面光回路、光子集成回路以及光电子集成回路等基本的光集成技术平台,分析了光有源器件中的光集成技术的演变趋势,并给出了对未来光集成技术发展的展望。     

在SDON中面向成本优化的虚拟光网络映射方法

结合软件定义光网络和光网络资源虚拟化的技术背景,对虚拟光网络成本优化问题进行了深入研究。在软件定义光网络中采用软件定义光网络基础服务架构和网络资源抽象的虚拟光网络服务架构,通过引入虚拟光网络的映射模型,提出了虚拟光网络映射策略和虚拟光网络协同映射规划方法,解决了面向成本优化的虚拟光网络映射方法,可为未来光网络虚拟化技术的应用提供技术支撑。     

光开关矩阵技术及其应用研究

光开关矩阵是智能光交叉连接设备和可重构光分插复用器核心技术,是构建自动交换光网络的基础.文章介绍了大规模商用的光开关矩阵的关键技术及其进展,详细分析了光开关矩阵在自动交换光网络中的应用.     

Na补偿的(Na,Bi)TiO3-Ba (Zr,Ti)O3无铅压电陶瓷

研究了(1-y)(Na0.5Bi0.5)TiO3-yBa(ZrxTi1-x)O3无铅压电陶瓷,获得压电应变常数d33高达185 pC/N的0.94(Na0.5Bi0.5)TiO3-0.06Ba(Zr0.055Ti0.945)O3压电陶瓷。添加0.04%摩尔过量Na2CO3的0.94(Na0.5Bi0.5)TiO3-0.06Ba(Zr0.055Ti0.945)O3高性能压电陶瓷d33高达195 pC/N。研究发现添加Na2CO3添加量至0.04%摩尔,Na起到软性添加物的作用,添加量超过0.04%,Na起到硬性添加物的作用.理论解释了过量Na的这一特性.为了降低介电损耗,对0.94(Na0.5Bi0.5)TiO3-0.06 Ba(Zr0.055Ti0.945)O3陶瓷进行了(Ce,Mn)掺杂改性研究。     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

离散系统差分方程的求解问题

讨论了差分方程经典解法的有关问题。对于可以用差分方程．y(k) an-1y(k-1) an-2y(k-2) … a0y(k-n)=f(k)(f(k)为因果信号)描述的离散因果系统直接用初始状态(即y(-1),y(-2),…,y(-n))来确定完全响应中齐次解的待定常数,而不必导出初始值(即y(0),y(1),…,y(n-1))。     

硫掺杂对ZnO热电性能的影响

采用固相反应法制备了ZnO1-xSx块体材料(0≤x≤0.05);通过对样品X射线衍射谱(XRD)、电导率和Seebeck系数的测量,研究了S掺杂对ZnO晶体结构及热电性能的影响。结果表明:所有试样均为六方纤锌矿结构。在573 K时,ZnO1-xSx(0相似文献   

不同物相二氧化钒间的相互转化及其相变性能研究

利用乙醇还原[VO(O2)2]-配合离子可以成功制备出VO2(B)纳米带;考察了VO2(B)在煅烧和水热条件下转化其它物相VO2的条件.结果表明,在惰性氛围中,VO2(B)在700℃的条件下煅烧2 h可以转化为VO2(M);在水热条件下,如果体系中无掺杂剂,VO2(B)可以转化成VO2(A);如果体系中存在掺杂剂(如钼酸),则VO2(B)转化为掺杂的VO2(M).在一步水热法制备VO2(M)过程中,选择掺杂剂是至关重要的,掺杂剂有利于形成掺杂VO2(M),使VO2(M)在水热条件下能够稳定存在.VO2(A)在惰性氛围中煅烧,发现VO2(A)也可以转化为VO2(M).不同物相VO2具有均一的带状形貌,初步探讨了VO2之间的转化机理.VO2(A)的相变温度为162.4℃;Mo掺杂VO2(M)的相变温度为53.7℃,说明掺杂Mo原子可以有效降低VO2(M)的相变温度,也表明Mo原子可以有效地进入VO2(M)晶格中.     

钕离子1.3μm波段放大特性和浓度猝灭研究

为了研究Nd3+的摩尔分数对1.3μm处荧光的影响,采用常规的熔融方法制备了钕离子掺杂的0.70TeO2-（0.30-x）WO3-xNd2O3(摩尔分数x为0.001,0.003,0.005,0.007,0.01）玻璃系统,得到了Nd3+ 1.3μm荧光光谱,同时还研究了荧光峰值波长的有效线宽和受激发射截面与Nd3+摩尔分数的关系。根据Dexter能量转移理论计算了Nd3+在碲酸盐玻璃中能量转移参量Cd,d(4F3/2,4I9/2→4I9/2,4F3/2)和Cd,a(4F3/2,4I9/2→4I15/2,4I15/2和4F3/2,4I9/2→4I13/2,4I15/2)值和相应发生浓度猝灭的临界距离Rd,d和Rd,a。结果表明,随着Nd3+的掺杂摩尔分数增加,荧光强度也逐渐增加,到0.005时达到最大;随后当Nd3+的摩尔分数大于0.005时,荧光强度逐渐降低。     

Thickness Dependent Properties of Relaxor-PbTiO(3) Ferroelectrics for Ultrasonic Transducers

The electrical properties of Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PMN-PT) based polycrystalline ceramics and single crystals were investigated as a function of scale ranging from 500 microns to 30 microns. Fine-grained PMN-PT ceramics exhibited comparable dielectric and piezoelectric properties to their coarse-grained counterpart in the low frequency range (<10 MHz), but offered greater mechanical strength and improved property stability with decreasing thickness, corresponding to higher operating frequencies (>40 MHz). For PMN-PT single crystals, however, the dielectric and electromechanical properties degraded with decreasing thickness, while ternary Pb(In(1/2)Nb(1/2))O(3)-Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PIN-PMN-PT) exhibited minimal size dependent behavior. The origin of property degradation of PMN-PT crystals was further studied by investigating the dielectric permittivity at high temperatures, and domain observations using optical polarized light microscopy. The results demonstrated that the thickness dependent properties of relaxor-PT ferroelectrics are closely related to the domain size with respect to the associated macroscopic scale of the samples.     

Synthesis, optical and electroluminescent properties of novel polyfluorene/carbazole-based conjugated polyelectrolytes and their precursors

A series of novel aminoalkyl-substituted fluorene/carbazole-based main chain copolymers with benzothiadiazole (BTDZ) of different contents: poly[3,6-(N-(2-ethylhexyl)carbazole)-(9,9-bis(3'-(N,N-dimethyl-amino)propyl)-2,7-fluorene)-4,7-(2,1,3-benzothiadiazole)] (PCzN-BTDZ) were synthesized by Suzuki coupling reaction. Through a postpolymerization treatment on the precursor polymer, a corresponding quaternized ammonium polyelectrolyte derivatives: poly[3,6-(N-(2-ethylhexyl)carbazole)-(9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)propyl)-2,7-fluorene)-4,7-(2,l, 3-benzothiadiazole)] dibromide (PCzNBr-BTDZ) were obtained. It was found that devices from such polymers with high work-function metal cathode such as Al showed similar device performance to that by using low work-function cathode such as Ba, indicating the excellent electron injection ability of these polymers. The efficient energy transfer from fluorene-carbazole segment to the narrow band gap BTDZ site for both the neutral and the quaternized copolymers was also observed. The addition of BTDZ into the polymer main chain can also improve polymer LED (PLED) device performance. When poly(3,4-ethylenedioxythiophene) (PEDOT)/poly(vinylcarbazole) (PVK) was used as an anode buffer, the external quantum efficiency of the copolymer PCzN-BTDZ1 was 0.99%, which was much higher than the copolymer PCzN without the incorporation of BTDZ in the same device configuration.     

Comparison of GaAs grown on standard Si (511) and compliant SOI (511)

Gallium arsenide (GaAs) films were grown by molecular beam epitaxy (MBE) on a (511) silicon substrate and a compliant (511) silicon-on-insulator (SOI) substrate. The top silicon layer of the compliant (511) SOI was thinned to ～1000 Å. The five inch diameter SOI wafer was created by wafer bonding. The GaAs (004) x-ray diffraction (XRD) reflection showed a 25% reduction in the full width half maximum (FWHM) for GaAs on a compliant (511) SOI as compared to GaAs on a silicon substrate. Cross section transmission electron microscopy (XTEM) clearly indicates a different dislocation structure for the two substrates. The threading dislocation density is reduced by at least an order of magnitude in the compliant (511) SOI as compared to the (511) silicon. XTEM found dislocations and damage was generated in the top silicon layer of the compliant SOI substrate after GaAs growth.     

基于FHQZn发光的新结构有机黄光器件

利用一种新型材料(E)-2-(2-(9H-fluoren-2-yl)vinyl)quinolato-Zinc(FHQZn)制备了一种新结构的黄光OLED,器件的结构为:indium-tinoxide(ITO)/4,4′,4″-{N,-(2-naphthyl)-N-phenylamino}-triphenylamine(2T-NATA)(15nm)/FHQZn(xnm)/4,4′-bis(2,2′-diphenylvinyl)-1,1′-biphenyl(DPVBi)(20nm)/2,2′,2″-(1,3,5-phenylene)tris(1-phenyl-1H-benzimidazole-(TPBi):6%factris(2-phenylpyridine)iridium(Ir(ppy)3)(45nm)/LiF(0.5nm)/Al,FHQZn作空穴传输层和黄色发光层,DPVBi作空穴阻挡层,TPBi中掺杂Ir(ppy)3作电子传输层;研究了发光层FHQZn的厚度对该器件的发光性能的影响。当FHQZn厚度x=25时,得到了效率和亮度最大的黄光器件,最大电流效率为1.31cd/A(at13V),最大亮度为5705cd/m2(at14V),此时色坐标为(0.4,0.5516)。