多孔硅发光的物理机制——纳米量子限制效应及表面态在发光中的作用

采用阳极氧化腐蚀的方法制备了多孔硅（ＰＳ），这种ＰＳ的微结构为纳米量级的，并具有光致发光特性，这无疑将对全硅光电子学的发展具有很大意义。根据大量实验与理论分析，提出了这种ＰＳ发光的物理机制：纳米量子限制效应和表面态及其物质在发光中的作用，从量子力学的薛定锷方程出发，用沟道势阱的近似模型，推导得到进入量子线的电子和空穴的能量势垒，ＰＳ的有效带宽Ｅ＝Ｅ＿０＋ΔＥ，对于Ｓｉ（Ｅ＿０＝１．１２ｅｖ）。完美地解释了目前在ＰＳ研究中的ＰＬ谱的篮移现象。     

SuperDense Quantum Teleportation

Recent advances in experimental technique make SuperDense Teleportation (SDT) possible only now, ten years after my first proposal at an ISI Torino summer conference on Quantum Computing. The effect uses remote state preparation to send more state-specifying parameters per bit than ordinary quantum teleportation (QT) can transmit. The SDT uses a maximally entangled state to teleport the relative phases of an n-dimensional state with equal amplitudes on every standard basis vector. For n greater than or equal to 3, the SDT sends more of these state-specifying parameters than QT. In the limit of large n the ratio is 2 to 1, hence the nomenclature by analogy with Super Dense Coding. Alice’s measurements and Bob’s transformations are far simpler than their corresponding operations in QT. The roles of Charles who chooses the state and Diana who deploys it are different than in QT. My discussion includes a brief review of the progress and possibilities of realization for several different experimental approaches around the world. This paper is the write-up of my remarks at the Festschrift conference for Anton Zeilinger, for many years a close collaborator in the Hampshire College NSF grant continuing our work with Mike Horne and Danny Greenberger started under Cliff Shull at MIT in the late 20th century.     

10W QCW operation of a proton implanted GaAlAs diode laser array

We report one thick layer of hard-baked photoresist mask.The laser array stripe pattern was defined by standard wet lithography.With this mask, a 10 W QCW(quasi-continuous wave) operation of a narrow proton implanted multiple stripe conventional single quantum well separate confinement heterostructure(SQW-SCH) GaAlAs diode laser array has been realized.These devices exhibit the lateral far-field radiation pattern of a phase-locked array of gain-guided semiconductor injection laser array. The twenty stripe laser array has a lateral far-field beam divergence full width at half maximum (FWHM) of less than 3°, and three twenty stripe laser array has a beam divergence in the plane of the junction of about 9°.     

微结构量子器件

微结构量子器件是八十年代中期伴随着微结构物理的发展而出现的一种新的半导体器件,这种器件以量子力学原理工作,具有常规“经典”器件无法比拟的优异特性。本文在简要介绍了微结构系统电子状态的基础上,较详细地描述了量子谐振隧道器件以及量子线和量子点激光器的基本原理、特点及其应用前景。     

基于混沌量子进化算法的单交叉口信号控制

城市道路各交叉口交通信号的配时优化和协同控制直接影响整个城市的交通状况.本文以单交叉口模型的交通信号控制问题为背景,构造了以单交叉口滞留的车辆数最少为目标的优化模型.用混沌量子进化算法进行仿真数据求解,得到实时控制的配时方案,并与其它算法的仿真结果进行比较,结果表明该算法对单交叉口的信号配时优化是非常有效的.     

Energy transfer and luminescent properties of Tb3+ and Tb3+, Yb3+ doped CNGG phosphors

In this work, calcium niobium gallium garnet (Ca₃Nb_1.6875Ga_3.1875O₁₂ - CNGG) ceramic samples single-doped with Tb³⁺ and co-doped with Tb³⁺ and Yb³⁺ ions were sintered by the solid-state reaction method. The structural characterization of the samples was carried out by X-ray diffraction measurements. The optimal concentration of Tb³⁺ ions corresponding to the maximum luminescence in the green spectral range in CNGG:x at% Tb (x = 0.1, 0.5, 1, 2, 3, 4, and 5) was determined to be 4 at%. The time-resolved luminescence of the ⁵D₄ level (Tb³⁺) in the CNGG:x at% Tb samples was analysed to explore the quenching mechanisms involved in the Tb³⁺ green emission. Co-doped CNGG:4 at% Tb,y at% Yb (y = 0.5, 2, 4, 6, 8, and 10) ceramics were prepared and investigated. It is shown that CNGG:4 at% Tb,y at% Yb phosphors exhibit intense green luminescence under ultra-violet (UV), visible (VIS), and near-infrared (NIR) excitation, thus demonstrating the presence of simultaneous down-conversion (DC) and up-conversion (UC) processes. The dependence of the UC luminescence intensity on the diode laser pumping power was measured and the results indicate a two-photon process based on cooperative energy transfer (CET). Under UV excitation, the lifetime of the ⁵D₄ (Tb³⁺) level slowly increases with increase of Yb³⁺ concentration, suggesting the energy transfer from Yb³⁺ to Tb³⁺ ions, while under NIR excitation, the lifetime of the ⁵D₄ (Tb³⁺) level decreases with increase of Yb³⁺ ions concentration, indicating the presence of a strong energy transfer from Tb³⁺ to Yb³⁺ ions. The highest energy transfer efficiency of ηET ≈42% was determined for the CNGG:4 at% Tb,10 at% Yb sample. The obtained results indicate that CNGG:(Tb³⁺, Yb³⁺) could be efficient new yellowish-green-emitting phosphors.     

Electronic Theory of Thermodynamic Adhesion inMetal/Ceramic Systems

ＥｌｅｃｔｒｏｎｉｃＴｈｅｏｒｙｏｆＴｈｅｒｍｏｄｙｎａｍｉｃＡｄｈｅｓｉｏｎｉｎＭｅｔａｌ／ＣｅｒａｍｉｃＳｙｓｔｅｍｓＬｉＪｉａｎ＇ｇｕｏ（李建国）（ＩｎｓｔｉｔｕｔｆｕｒＮｉｃｈｔｍｅｔａｌｌｉｓｃｈｅＷｅｒｋｓｔｏｆｆｅ，ＴｃｈｎｉｓｃｈｅＵ...