Photon-Assisted Electron Transport for a λ-shaped Carbon Nanotube Junction

We theoretically study the electron transport properties for two coupled single-walled caxbon nanotube quantum dots connected to metallic electrodes under the irradiation of an external electromagnetic field at low tempera- tures. Using the standaxd nonequilibrium Green＇s function techniques, we examine the time-averaged transmission coefficient and linear conductance. It is shown that by some numerical examples, the photon-assisted inter-dot coupling causes Fano resonance and the conductance of the system is sensitive to the external field parameters. The transport dependence on the external field parameters may be used to detect the high-frequency microwave irradiation.     

Calculation of Particle-Number Susceptibility of QED3 at Finite Temperature

Based on the external field approach and the differential form of Ward identity, we derive a more compact formula for the particle-number susceptibility in QED3 at finite temperature. Using the zero frequency approximation the numerical value of the particle-number susceptibility is calculated in the Dyson-Schwinger approach for the case that the number of fermion flavours equals one and two, respectively. An enhanced fluctuation of the particlenumber density is observed across the transition temperature, which should be an essential characteristic of chiral phase transition in QED3.     

二维正方光子晶体完全禁带与导波特性数值分析

以简单二维正方排列的光子品体为例,计算分析了完全禁带随介质填充率和介质折射率比变化出现的条件和规律,结果显示对两者同时进行调谐是获取完全禁带的最佳途径,选取晶格常数为0.7 μm,介质填充率0.5,介质折射率比为4时,在光子晶体中引人线缺陷后,对处于完全禁带中的波长为1.55μm的光显示良好的导波特性.     

基于PVK∶NPB掺杂体系的有机电致发光器件的性能

利用溶液旋涂的方法,通过改变复合功能层中poly(N-vinylcarbazole)(PVK)和N,N′-bis-(1-naph-thyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine(NPB)的质量比,制备结构为indium-tin-oxide(ITO)/PVK:NPB/2,9-dimenthyl-4,7-diphenyl-1,10-phenanthroline(BCP)/Mg:Ag的有机电致发光器件,并对器件的电致发光特性进行了表征。研究结果表明,当复合功能层中PVK和NPB的质量比为1:1时器件性能最好,在该器件的电致光谱中,除了NPB的本征谱峰外,在长波方向还出现了一个位于640nm处的谱峰,这是PVK和NPB产生的电致激基复合物发光,并且随着驱动电压的增加,电致激基复合物的发光强度也相对增强。     

一种Λ型吡啶碘盐的合成和晶体结构

近年来光纤通讯、激光二极管、光信号处理及光计算等领域的快速发展极大地推动了非线性光学的研究[1-3].新型非线性光学材料的设计及合成是该领域人们关注的热点之一[1,4,5].     

钛白粉清洁生产工艺探索

本文以清洁生产理念为基础，提出了钛白粉生产工艺的清洁生产方案，作出相应的三废和经济分析，对解决生产工艺中造成的污染和因此而产生的经济损失问题进行了探讨。     

BIFURCATION AND STABILITY ANALYSIS FOR LIQUID SURFACES

A more comprehensive discussion on the bifurcation problems for the shape of liquidsurfaces is made in this paper.The necessary conditions for bifurcation are given,and thebifurcating solutions near bifurcation points can be obtained by perturbation technique.Finally the stability of the bifurcating states is analyzed by means of the principle ofminimum potential energy.     

微分环的研制

微分环用于测量纳秒级脉冲电流。本文通过理论分析导出影响微分环性能的特征参数及设计原则。按上述原则制成的微分环经同轴式模拟试验装置验证及理论计算,证明其性能优良,上升时间小于1ns。