中国科学院上海光学精密机械研究所

<正>激光与光电子材料研究发展中心中国科学院上海光学精密机械研究所激光与光电子材料研究发展中心从事晶体材料研究已有40多年的历史,研究方向主要包括:激光晶体、宽禁带半导体衬底晶体、大尺寸蓝宝石晶体、新型发光勺闪烁晶体、光学及光电功能晶体材料等。目前,中心可以提供的主要产品包括:1.激光晶体Ti:Al2O3,Nd:YLF,Nd:YAG,Cr:YAG,Nd:YVO4,Nd,GGG,Yb.YAG,Yb:GSO等;2.高温超导薄膜基片MgO,LaAlO3,SrTiO3,LAST,NdGaO3,YSZ等,3.磁性薄膜与铁电薄膜基片     

"弱电解质的电离"创新教学设计与反思

"弱电解质的电离"教学设计主要由5个环节组成,重点是教学流程的创新设计,由5个师生课堂活动构成,这样创新教学设计对实施课堂有效教学起着重要的作用.     

微型惯性仪器的展望

本文介绍了惯性仪器的应用前景、技术要求和市场预测。对微型机械陀螺仪和加速度计，作了简要的描述。对微型光学陀螺仪，在工作原理、结构、材料和工艺等方面进行了初步探讨。随着微米／纳米技术的进一步发展，它们将成为光电子集成的微型仪器     

高超声速三维化学非平衡流动简化NS方程数值解

本文研究用时间稳定法求解高超声速三维化学非平衡流动简化ＮＳ方程，把整个非平衡流体动力学问题分裂为流体力学问题和化学问题。流体力学与化学问题之间的耦合通过迭代方式加以处理。考虑高温空气分解与电离，七个化学组元，并认为化学反应是以有限速率进行的．差分格式采用无自由参数的混合反扩散格式，激波及壁面处理应用特征线理论．对来流攻角为１０°，马赫数为２６，飞行高度为８５ｋｍ的钝锥体，给出了流场参数和物面加热率的数值计算结果．     

High-l Rydberg States＇ Interference Using a Double-Pulse Electric Field

The interference behavior of high-1 Rydberg states is investigated in external fields. We prepare high-l states from an initial excited ns Cs Rydberg state by applying one electric-field pulse. The interference between the initial ns state and the high-I states is investigated by two time-delayed short electric-field pulses. The state selective field ionization technique is used to measure the transfer ratio versus the field pulses parameters. The visibility of interference is defined to describe interference and the results show that a relative long duration of electric-field pulse will weaken the interference.     

TixSb2Te Thin Films for Phase Change Memory Applications

Sb2 Te films with different Ti contents （TixSb2 Te） are derived via the target-attachment method by using the magnetron sputtering technique. The effects of the Ti content on the phase change characteristics and the microstructures are investigated by x-ray diffraction, x-ray photoelectron spectroscopy, scanning electron microscopy and atom force microcopy. Resistance-temperature measurements are carried out to reveal the enhanced crystallization temperature of TixSb2 Te films, indicating a better thermal stability in such films. Both the activation energy and the temperature for 10 y data retention increase with increasing the concentration of Ti. It indicates that the crystallization of the amorphous Sb2 Te film could be suppressed by the introduction of Ti. The improvement of crystallization temperature and the thermal stability of the amorphous Sb2 Te film results from the introduction of Ti in Sb- Te bond that decreases the binding energy of Sb 4d and Te 4d.     

X射线光电子能谱与13C核磁共振在生物质碳表征中的应用

近年来,生物质碳(biochar)作为新型吸附剂被广泛研究。但由于制备biochar的生物质原料和热解温度的不同,使biochar的结构和组成存在差异,从而影响其对污染物的吸附。目前关于biochar的结构和组成的研究还不够全面。因此,结合了能谱与光谱分析的手段,对biochar的结构和组成进行了深入的分析。选取木质类(柳树枝条)和草类(水稻秸秆)作为原料,分别在不同热解温度(300,450和600℃)下制得biochars,并对biochars样品进行元素分析、X射线光电子能谱分析(XPS)和固态13 C核磁共振(13 C NMR)研究,以阐明不同热解温度和生物质来源的biochars的结构和组成。结果显示:biochar的H/C,O/C和(O+N)/C的比值随着热解温度的升高而降低;草类biochar比木质类biochar具有更高的灰分含量和表面极性;木质类biochar的矿物主要分布在样品颗粒内部,其表面被有机质覆盖,而草类biochar部分矿物暴露在样品颗粒表面;13 C NMR显示低温制得的biochar主要由芳香碳、脂肪碳、羧基和羰基碳组成,高温制得的biochar主要由芳香碳组成,且低温制得biochars中,木质类biochars比草类biochars含有更高的木质素的残留碳结构,这是由于木质类biochars原材料中含有更高的木质素。     

Increased work function in PEDOT:PSS film under ultraviolet irradiation

An increase of work function （0.3 eV） is achieved by irradiating poly（3,4-ethylenedioxythiophene）：poly（styrene sul- fonate） （PEDOT：PSS） film in vacuum with 254-nm ultraviolet （UV） light. The mechanism for such an improvement is investigated by photoelectron yield spectroscopy, X-ray photo electron energy spectrum, and field emission technique. Sur- face oxidation and composition change are found as the reasons for work function increase. The UV-treated PEDOT：PSS film is used as the hole injection layer in a hole-only device. Hole injection is improved by UV-treated PEDOT：PSS film without baring the enlargement of film resistance. Our result demonstrates that UV treatment is more suitable for modifying the injection barrier than UV ozone exposure.     

Investigation on the influence of atomic potentials on the above threshold ionization

We systematically investigate the influence of atomic potentials on the above-threshold ionization （ATI） spectra in one-dimensional （1D） cases and compare them with the three-dimensional （3D） case by numerically solving the time-dependent Schrrdinger equation. It is found that the direct ionization plateau and the rescattering plateau of the ATI spectrum in the 3D case can be well reproduced by the 1D ATI spectra calculated from the supersolid-core potential and the soft-core potential, respectively. By analyzing the factors that affect the yield of the ATI spectrum, we propose a modified-potential with which we can reproduce the overall 3D ATI spectrum. In addition, the influence of the incident laser intensities and frequencies on the ATI spectra calculated from the proposed modified potential is studied.