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Effects of deposition pressure and plasma power on the growth and properties of boron-doped microcrystalline silicon films

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Chinese physics B 2008年第4期17卷 1394-1399页

作者：陈永生杨仕娥汪建华卢景霄郜小勇谷景华郑文赵尚丽 Key Laboratory of Material physics Department of PhysicsZhengzhou University Institute of Plasma physics Chinese Academy of Sciences depart of Materials Science and Engineering Wuhan Institute of Technology

Using diborane as doping gas, p-doped μc-Si：H layers are deposited by using the plasma enhanced chemical vapour deposition （PECVD） technology. The effects of deposition pressure and plasma power on the growth and the properties of μc-Si：H layers are investigated. The results show that the deposition rate, the electrical and the structural properties are all strongly dependent on deposition pressure and plasma power. Boron-doped μc-Si：H films with a dark conductivity as high as 1.42 Ω^-1·cm^-1 and a crystallinity of above 50% are obtained. With this p-layer, μc-Si：H solar cells are fabricated. In addition, the mechanism for the effects of deposition pressure and plasma power on the growth and the properties of boron-doped μc-Si：H layers is discussed.

关键词： boron-doped μc-Si:H films thin film solar cells Raman crystallinity dark conductivity

Effect of carbon addition on microstructure and mechanical properties of Ti-based bulk metallic glass forming alloys

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中国有色金属学会会刊：英文版 2005年第4期15卷 727-732页

作者：孙玉峰王育人魏炳忱李维火石灿鸿 National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences depart ment of physics and Materials Science City University of Hong Kong

A kind of novel Ti-based composites was developed by introducing different amounts of carbon element to the Ti50Cu23Ni20Sn7 bulk metallic glass forming alloys. The thermal stability and microstructural evolution of the composites were investigated. Room temperature compression tests reveal that the composite samples with 1% and 3%（mass fraction） carbon additions have higher fracture strength and obvious plastic strain of 2195MPa, 3.1% and 1913MPa, 1.3% respectively, compared with those of the corresponding carbon-free Ti50Ni20Cu23Sn7 alloys. The deformation mechanisms of the composites with improved mechanical properties were also discussed.

关键词：钛铸造工艺合金机械结构

半导体量子点材料在Nd∶YAG激光辐照下的非线性光学效应(英文)

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光学精密工程 2011年第2期19卷 228-236页

作者： KUMBHAKAR P Nanoscience Laboratory Depart ment of PhysicsNational Institute of Technology

使用10 ns脉冲调QNd∶YAG激光器Z-scan技术测量了化学合成的无掺杂硫化锌量子点(QDs)以及掺Mn2+硫化锌量子点(QDs)的非线性光学特性,并使用透射电镜技术(TEM)以及X射线衍射法(XRD)表征合成材料的纳米结构。在室温下,分别利用UV-VIS分光... 详细信息

使用10 ns脉冲调QNd∶YAG激光器Z-scan技术测量了化学合成的无掺杂硫化锌量子点(QDs)以及掺Mn2+硫化锌量子点(QDs)的非线性光学特性,并使用透射电镜技术(TEM)以及X射线衍射法(XRD)表征合成材料的纳米结构。在室温下,分别利用UV-VIS分光光度计和分光荧光计测量了人工合成QDs胶体溶液的线性光学吸收特性以及光致发光的发射特性。样品的吸收特性表明,由于量子限制效应的影响,样品的截止吸收低于硫化锌的截止吸收。样品的光致发光特性显示,掺Mn2+的硫化锌样品显示出明显的光致发光现象,发射峰大约在580 nm;而无掺杂的硫化锌样品在紫外区辐射,发射峰大约在365 nm。对样品的UV-VIS吸收特性分析和TEMXRD分析表明,硫化锌样品的平均粒度(半径)大约为1.2 nm。分析开放光圈(OA)Z-scan技术得到的实验数据,发现在1 064 nm处两种试验样品都会发生四光子吸收(FPA)现象。拟合实验数据得到了两种试验样品的FPA系数以及FPA横截面,结果表明,ZnS QD的FPA横截面的计算值是4.9×***-3,比硫化锌的FPA横截面大了5个数量级,而且人工合成的ZnS QD也有光学限制的性质。掺Mn2+离子的样品具有大的FPA横截面和在可见光区有高的发光效率这两个特点,使得该材料适合用于多光子荧光成像。

关键词：半导体材料 ZnS量子点非线性光学特性多光子吸收 ZnS掺杂 Mn掺杂

Transferring and Bounding Single Photon in Waveguide Controlled by Quantum Node Based on Atomic Ensemble

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Communications in Theoretical physics 2009年第9期52卷 500-506页

作者： LU Jing DONG Hui KUANG Le-Man Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education and Depart- ment of Physics Hunan Normal University Changsha 410081 China Institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China

We study the scattering process of photons confined in a one-dimensional optical waveguide by a laser controlled atomic ensemble. The investigation leads to an alternative setup of quantum node controlling the coherent transfer of single photon in such one dimensional continuum. To exactly solve the effective scattering equations by using the discrete coordinate approach, we simulate the linear waveguide as a coupled resonator array at the high energy limit. We generally calculate the transmission eoet^cients and its vanishing at resonance reflects the good controllability of our scheme. We also show that there exist two bound states to describe the localize photons around the cavity.

关键词： one-dimensional waveguide single photon bound states

CdZnTe平面探测器对低能X/γ射线的光谱响应

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光学学报 2009年第11期29卷 3072-3077页

作者：徐亚东介万奇查刚强高俊宁王涛傅莉 Paul Sellin 西北工业大学材料学院陕西西安710072 depart ment of physics University of Surrey

基于3片不同条件下生长的CdZnTe晶片制备出平面电极(Planar)探测器CZT1、CZT2及CZT3。分析室温下3个探测器在不同场强作用下对低能X/γ射线的光谱响应,并结合相应晶体材料的载流子迁移特性和掺杂剂的浓度以及存在状态,归纳影响探测器分... 详细信息

基于3片不同条件下生长的CdZnTe晶片制备出平面电极(Planar)探测器CZT1、CZT2及CZT3。分析室温下3个探测器在不同场强作用下对低能X/γ射线的光谱响应,并结合相应晶体材料的载流子迁移特性和掺杂剂的浓度以及存在状态,归纳影响探测器分辨率的原因。掺杂In浓度高的探测器CZT1,由于材料中存在的深能级缺陷Cdi2+,作为电子的俘获中心,影响了载流子的收集效率,进而降低了探测器的能量分辨率;掺杂In浓度低的探测器CZT2对不同能量X/γ射线均具有较好的能量分辨率;而Al掺杂探测器CZT3,由于Al间隙原子Ali的存在作为电子的散射中心,最终影响了收集效率及能量分辨率。

关键词： CdZnTe平面探测器 X/γ射线能量分辨率载流子迁移特性散射

Deconfinement phase transition in neutron star matter

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Chinese physics C 2009年第S1期33卷 61-63页

作者：李昂彭光雄 Lombardo U department of physics and Institute of Theoretical physics and Astrophysics Xiamen University Dipartimento di Fisica e Astronomia Catania University China Center of Advanced Science and Technology (World Laboratory) Institute of High Energy physics Chinese Academy of Sciences Phys. depart. of Graduate University Chinese Academy of Sciences Laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare

The transition from hadron phase to strange quark phase in dense matter is investigated. Instead of using the conventional bag model in quark sect, we achieve the confinement by a density-dependent quark mass derived from in-medium chiral condensates, with a thermodynamic problem improved. In nuclear slot, we adopt the equation of state from Brueckner-Bethe-Goldstone approach with three-body force. It is found that the mixed phase can occur, for reasonable confinement parameter, near the normal saturation density, and transit to pure quark matter at 4—5 times the saturation, which is quite different from the previous results from other quark models that pure quark phase can not appear at neutron-star densities.

关键词： phase transition the density-dependent quark model three-body force

Microindentation as a perspective method for determination of mechanical properties of ribbon metallic glasses

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广东有色金属学报 2005年第2期15卷 185-187页

作者： Victor A.Feodorov Inga Y.Permyakova Andrey N. Kapustin depart ment of General physics Derzhavin Tambov State University Tambov 392622 Russia

Conditions of gauging of true microhardness of thin ribbons metallic glasses (MG) with the count of their depth are established. For the first time the method of a indentation was approved for an assessment of crack resistance of MG. The behavior of parameterK_ Ic is found in a interval of temperature of viscous-brittle transition down to the beginning of volumetric crystallization of MG. The estimation method of temperature of viscous - brittle transition is offered at the microindentation of annealing ribbon on an elastic substrate.

关键词：玻璃金属材料结构参数结晶化

Influence of small dozes ultra-violet radiation on motion of dislocationin alkali-halide crystals

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广东有色金属学报 2005年第2期15卷 147-148页

作者： Victor A.Feodorov Tatjana . N.Plushnikova Andrey V.Chivanov Margarita V.Chemerkina Roman A.Kirillov depart ment of general physics Derzhavin Tambov State University Tambov State University Tambov 392622 Russia

The purpose of this work was research into influence of ultra-violet radiation on size of run of regional and screw dislocations in beams of dislocation sockets, formed at indentation surface of alkali-halide crystals. In experiments it was used crystals NaCl, with the quantitative maintenance of impurity 10-2 -10-3weight%, the wave length of UV-radiation λ=250 nanometers, the sizes of samples 10mm× 20mm× 2mm,temperature of samples was constant T=290 *** is established that indentation and the simultaneous irradiation of samples a ultraviolet is increases size of run of head dispositions in dislocation sockets..It is marked, that influence UV-radiation nonequivalence for various times of an exposition. At small times (till 5 minutes) the size of run grows. The length of beams increases on ～ 50 %. At the further increase in time of influence of a ultraviolet the length of beams is reduced till the sizes corresponding stressing without an irradiation (Figs. 1, 2, 3). The effect is observed on dislocation beams of regional and screw orientations and most expressed at small loadings (in our experiments-10 grams) (Fig. 3).Observable effects are explained from positions dislocation-exciton interactions. At UV-radiation exciton cooperates with the charged step on a disposition, causing movement of a step along a disposition on one internuclear distance. Due to this interaction overcoming by a disposition of a grid of stoppers is *** times of endurance cause a relaxation of pressure directly in a print that provides convertible movement of dispositions in area of a print and as consequence, reduction of length of beams of dislocation sockets.

关键词：碱性卤化物晶体结构非金属元素

Two Future Space X-ray Astronomy Missions of China:HXMT and WIMS

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Two Future Space X-ray Astronomy Missions of China:HXMT and ...