XGS—12型高速电影摄影机

XGS-12型摄影机是西安光机所新近推出的又一种16mm棱镜补偿式高速电影摄影机,其画幅尺寸为7.5×10.4mm~2时的最高拍摄频率为11000fps。该机性能优异,附件齐全,本文对该机将从光学系统摄影机和电控制系统三个部分加以介绍。     

激光产生温稠密物质的微观动力学过程及状态诊断

随着大型激光装置的建立和精密测量技术的发展,强激光与固体相互作用成为实验室产生温稠密物质的一个重要手段。温稠密物质的结构复杂性、瞬态性和非平衡性给理论建模和实验测量带来了巨大挑战。本文系统介绍了激光产生温稠密物质的实验手段和理论模拟方法方面的重要进展,分析了其中的电子激发动力学、电子-离子能量弛豫过程、离子动力学等物理过程,总结了温稠密物质状态诊断的实验技术和理论方法,并论述了激光产生温稠密物质的发展趋势。     

HgCdTe薄膜的输运特性及其应力调控

窄禁带直接带隙半导体材料碲镉汞(Hg1–xCdxTe)是一种在红外探测与自旋轨道耦合效应基础研究方面都具有重要应用意义的材料.本文对单晶生长的体材料Hg0.851Cd0.149Te进行阳极氧化以形成表面反型层,将样品粘贴在压电陶瓷上减薄后进行磁输运测试,在压电陶瓷未加电压时观察到了明显的SdH振荡效应.对填充因子与磁场倒数进行线性拟合,获得样品反型层二维电子气的载流子浓度为ns=1.25×10^16m^-2.在不同磁场下,利用压电陶瓷对样品进行应力调控,观测到具有不同特征的现象,分析应是样品中存在二维电子气与体材料两个导电通道.零磁场下体材料主导的电阻的变化应来源于应力导致的带隙的改变;而高场下产生类振荡现象的原因应为应力导致的二维电子气能级的分裂.     

应变Ge空穴有效质量的各向异性与各向同性

在利用k·p微扰理论获得应变Ge/Si_1-xGe_x价带E（k）-k关系的基础上,研究得到了（001）,（101）,（111）面应变Ge/Si_1-xGe_x沿不同晶向及各向同性的价带空穴有效质量.结果显示,应变Ge/Si_1-xGe_x沿各晶向的带边有效质量随应力增大而减小,且沿[010]晶向最小;子带空穴有效质量在应力较大时变化不明显,并且在数值上与带边空穴有效质量相差不大.最后利用各向同性有效质量与文献结果进行比对,验证了结果的正确性.     

Interfacial electronic structure and magnetoelectric effect in M/BaTiO3 (M=Ni,Fe) superlattices

Using first-principles density functional theory, we investigate the interfacial electronic structure and magnetoelectric effect in M/BaTiO₃ (M=Ni, Fe) superlattices, and find a novel type of interfacial magnetoelectric coupling mechanism in the Ni/BaTiO₃ interface. This magnetoelectric effect is determined by the change of magnetic moments on Ni atoms near the interface, instead of the induced moments on interfacial Ti atoms in Fe/BaTiO₃ system, which is also distinguished from the spin-polarized carriers screening mechanism. The underlying physics is the strong interface bonding and the pdσ-type magnetic interactions between Ni 3d and O 2p spins. Furthermore, there exists an extraordinary intralayer oscillation of magnetic moments within the Ni layers, which may be observed in experiments.     

An intermediate distribution between Gaussian and Cauchy distributions

In this paper, we construct an intermediate distribution linking the Gaussian and the Cauchy distribution. We provide the probability density function and the corresponding characteristic function of the intermediate distribution. Because many kinds of distributions have no moment, we introduce weighted moments. Specifically, we consider weighted moments under two types of weighted functions: the cut-off function and the exponential function. Through these two types of weighted functions, we can obtain weighted moments for almost all distributions. We consider an application of the probability density function of the intermediate distribution on the spectral line broadening in laser theory. Moreover, we utilize the intermediate distribution to the problem of the stock market return in quantitative finance.     

大学物理实验开放式教学的实现

提出了开展大学物理实验开放式教学的具体实现方法及步骤。     

紫外波段CH2I2分子的光解离动力学研究

利用离子速度成像方法,研究CH2I2分子在277—305nm范围内若干波长处的光解离动力学.通过同一束激光经(2+1)共振多光子电离(REMPI)过程探测光解碎片I(2P32)和I(2P12),得到了不同激发波长处的离子速度分布图像,从而获得CH2I2光解产物的能量分配和角分布.实验发现,碎片CH2I自由基有很高的内能激发,约占总可资用能的80%,该能量分配可以较好地用冲击模型来解释.实验还发现,产物I(2P32)和I(2P12)具有很不相同的平动能分布,结合所得到的碎片能量分配和角分布,我们对碎片I(2P32)和I(2P12)生成机理进行了分析,指出CH2I2分子电子激发态的绝热和非绝热解离决定了碎片的平动能分布. 关键词： CH2I2 离子速度成像 绝热和非绝热解离     

New figuring model based on surface slope profile for grazing‐incidence reflective optics

Surface slope profile is widely used in the metrology of grazing‐incidence reflective optics instead of surface height profile. Nevertheless, the theoretical and experimental model currently used in deterministic optical figuring processes is based on surface height, not on surface slope. This means that the raw slope profile data from metrology need to be converted to height profile to perform the current height‐based figuring processes. The inevitable measurement noise in the raw slope data will introduce significant cumulative error in the resultant height profiles. As a consequence, this conversion will degrade the determinism of the figuring processes, and will have an impact on the ultimate surface figuring results. To overcome this problem, an innovative figuring model is proposed, which directly uses the raw slope profile data instead of the usual height data as input for the deterministic process. In this paper, first the influence of the measurement noise on the resultant height profile is analyzed, and then a new model is presented; finally a demonstration experiment is carried out using a one‐dimensional ion beam figuring process to demonstrate the validity of our approach.