Y稳定的ZrO_2基体上YBa_2Cu_3O_7／SrTiO_3／YBa_2Cu_3O_7异质外延三层膜的制备、超导性能和显微结构

采用磁控溅射方法在（１００）ＹＳＺ基底上沉积了ＹＢａ２Ｃｕ３Ｏ７／ＳｒＴｉＯ３／ＹＢａ２Ｃｕ３Ｏ７异质外延三层膜，利用交流磁化率和四引线电阻测量的方法确定了三层膜的超导性能，利用Ｘ射线衍射和透射电子显微镜研究了三层膜的结构特征．研究结果表明，膜层的结晶质量较好，临界转变温度Ｔｃ在８３．Ｋ和８６．７Ｋ之间．ＹＢＣＯ膜层中的绝大多数甚至全部）晶粒为Ｃ取向，在有些膜中只存在少量的ａ或ｂ取向的ＹＢＣＯ晶粒．三层膜中层界面比较清晰但不十分平整．在膜／基界面处有８－１０ｎｍ厚的过渡层，它由多晶的ＢａＺｒＯ３组成．膜层和（１０）ＹＳＺ基底之间具有如下的外延生长关系ＹＳＺ［００１］／／ＹＢＣＯ［１１０］／／ＳｒＴｊＯ３［１１０］；ＹＳＺ（１００）／／ＹＢＣＯ（００１）／／ＳｒＴｉＯ３（００１）．     

一种由自由电子能带模型计算费米能级的方法

对面心立方（fcc)、体心立方（bcc)和六角密堆积（hcp)三种不同结构的晶体,在假设它们的原胞中包含8个价电子并将价电子近似为自由电子的情况下,采用“自由电子气理论”和“自由电子能带模型”,研究其根据费米球确定的费米能级EF与根据自由电子能带模型计算的平均键能Em。研究结果表明,由自由电子能带模型计算所得3种不同结构晶体（因而电子密度也不一样）的平均键能Em等于各自自由电子系统的费米能级EF。平均键能Em是我们在异质结带阶理论计算中建议的一种参考能级,研究结果在深化对平均键能Em物理实质认识的同时,提供了一种借助于自由电子能带模型计算自由电子系统费米能级EF的新方法。     

沉积态铀薄膜表面氧化的X射线光电子能谱

含铀(U)薄膜在激光惯性约束聚变的实验研究中有重要的用途.研究其在不同气氛下的氧化性能可以为微靶制备、储存及物理实验提供关键的实验数据.通过超高真空磁控溅射技术制备了纯U薄膜及金-铀(Au-U)复合平面膜,将其在大气、高纯氩(Ar)气及超高真空度环境中暴露一段时间后,利用X射线光电子能谱仪结合Ar~+束深度剖析技术考察U层中氧(O)元素分布及价态,分析氧化产物及机理.结果显示,初始状态的U薄膜中未检测到O的存在.Au-U复合薄膜中的微观缺陷减弱了Au防护层的屏蔽效果,使其在3周左右时间内严重氧化,产物为U表面致密的氧化膜及缺陷周围的点状腐蚀物,主要成分均为二氧化铀(UO_2).在高纯Ar气中纯U薄膜仅暴露6 h后表面即被严重氧化,生成厚度不均匀的UO_2.在超高真空度环境下保存12 h后,纯U薄膜表面也发生明显氧化,生成厚度不足1 nm的UO_2.Ar~+束对铀氧化物的刻蚀会因择优溅射效应而使UO_2被还原成非化学计量的UO_(2-x),但这种效应受O含量的影响.     

激光诱导等离子体光谱技术的实验装置进展

简述了近几年来国内外激光诱导等离子体技术的发展情况,着重从实验装置的几个方面进行分析,包括激光能源、采光装置、接收装置。另外对双路脉冲激光蒸发、激发技术进行了简短的讨论。     

a-Si:H结的横向光生伏特效应

本文通过理论分析研究了a-Si:H结中横向光生伏特效应的定态与瞬态特性。所得结果表明理论与实验非常符合。值得注意的是,按理论关系应用常规不掺杂a-Si:H特性值估算的两个重要参数(样品中的薄层电阻1/σ_s和传输时间T_m)均比由实验得出的值大得多。基于合理的分析。我们认为在a-Si:H层中平行于结输运的电子可能具有异乎寻常高的载流子迁移率。 关键词：     

从人文素质教育角度，探讨大学语文与思想品德整合的现实性和实施途径

如何利用有限的课时，使人文素质教育取得最大的教育效果，一直是理工科院校努力探索解决的一个重要问题。本文从大学生精神成人的角度，以普世价值观为准则，对大学语文和思想品德课的课程目标进行分析，探索如何把品德课中抽象的理论和大学语文中的生动形象结合起来，力图用熏陶感染代替空洞说教，使学生更容易接受，更好实现教育功能。     

Design and Application of a Near Field Microwave Antenna for the Spin Control of Nitrogen-Vacancy Centers

Controlled manipulation of the electron spin by means of a microwave field is investigated. The near magnetic field generated by a copper wire antenna is measured experimentally and simulated theoretically, and the optimum antenna length and position are obtained. By measuring the change in the fluorescence of nitrogen-vacancy （N-V） centers in diamond after excitation with a 532 nm continuous wave laser at room temperature, it is verified that the spin of the N-V center can be effectively controlled by the microwave field.     

Electrochemical Deposition and Properties of ZnTe Nanowire Array

Pulsed electrodeposited technique is applied to fabricate ZnTe nanowire arrays with different diameters into the anodic alumina membrane in citric acid solution. The x-ray powder diffraction, scanning electron microscopy and transmission electron microscopy indicate that the high ordered, uniform and single-crystalline nanowires have been fabricated. The optical absorption spectra of the nanowire array show that the optical absorption band edge of the ZnTe nanowire array exhibit a blue shift compared with that of bulk ZnTe, and the nonlinear current-voltage characteristic is observed.     

X-ray observations of tungsten wire array Z-pinch implosions on QiangGuang-1 facility

Z-pinch experiments with two arrays consisting, respectively, of 32 4-μm- and 6-μm-diameter tungsten wires have been carried out on QiangGuang-1 facility with a current rising up to 1.5MA in 80ns. At early time of implosion, x-ray framing images show that the initial emission comes from the central part of arrays, and double clear emission rings, drifting to the anode and the cathode at 5×10⁶cm/s and 2.4×10⁷cm/s respectively, are often produced near the electrodes. Later, in a 4-μm-diameter tungsten wire array, filamentation caused by ohmic heating is prominent, and more than ten filaments have been observed. A radial inward shift of arrays starts at about 30\,ns earlier than the occurrence of the x-ray peak power for both kinds of arrays, and the shrinkage rate of emission region is as high as 1.7×10⁷cm/s in a 4-μm-diameter tungsten wire array, which is two times higher than that in a 6-μm one. Emission from precursor plasmas is observed in implosion of 6-μm-diameter tungsten wire arrays, but not in implosion of a 4-μm-diameter tungsten wire array. Whereas, in a 4-μm-diameter tungsten wire array, the soft x-ray emission shows the growth of m=1 instability in the plasma column, which is caused by current. The reasons for the discrepancy between implosions of 4-μm- and 6-μm-diameter tungsten wire arrays are explained.