Relationship Between Differential Interference Angle and Parameter of Experiment in Molecular Beam

Collisional quantum interference (CQI) was observed in the intramolecular rotational energy transfer in the experiment of the static cell, and the integral interference angles were measured. To observe more precise information, the experiment in the molecular beam should be taken, from which the relationship between the differential interference angle and the scattering angle can be obtained. In this paper, the theoretical model of CQI is described in an atom-diatom system in the condition of the molecular beam, based on the first-Born approximation of time-dependent perturbation theory, taking into accounts the long-range interaction potential. The method of observing and measuring correctly the differential interference angle is presented. The changing tendency of the differential interference angle with the impact parameter and relative velocity is discussed. The changing tendencies of the differential interference angle with the parameter of experiment in the molecular beam, including the impact parameter and the velocity are discussed. This theoretical model is important to understand or perform the experiment in the molecular beam.     

Collisional quantum interference on rotational energy transfer： physical interpretation of the differential interference angle

Collisional quantum interference （CQI） on the intramolecular rotational energy transfer is observed in an experiment with a static cell, and the integral interference angles are measured. To obtain more accurate information, an experiment with a molecular beam is carried out, and thereby the relationship between the differential interference angle and the scattering angle is obtained. Based on the first-Born approximation of time-dependent perturbation theory, the theoretical model of CQI is developed in an atom-diatom system in the condition of the molecular beam, with the long-range interaction potential taken into account. The method of measuring correctly the differential interference angle is presented. The tendencies of the differential interference angle changing with the impact parameter and rel- ative velocity are discussed. The theoretical model presented here is important for understanding or performing the experiment in the molecular beam.     

深入理论研究碰撞转动传能量子干涉效应的微分干涉角

分子内部转动传能的静态池实验观察到了碰撞量子干涉效应(CQI),并且测得积分干涉角,为了获得更加精确的分子内部转动传能的碰撞量子干涉效应信息,实验就必须要采用分子束实验进行.本文理论上采用各项异性相互作用势,应用含时微扰理论的一级波恩近似,假想在分子束实验的条件下,建立在原子—双原子分子体系中碰撞量子干涉的理论模型.理论上推导出微分干涉角具体表达式,通过计算定性地讨论了微分干涉角随着碰撞参数、速率等的变化趋势,同时初步探讨了实验的正确观测途径,得出了采用分子束进行实验观测的实验方法,为进一步进行分子束实验提供了理论基础,对实验的进行起到了一定的借鉴作用.     

转动传能量子干涉效应:干涉角影响因素的研究

碰撞转动传能中存在量子干涉效应已经在静态池实验中被观测到,并且积分角也能被测量.利用分子束实验可得到转动传能更准确的信息,进而得到影响干涉角的的具体因素.文中利用一阶含时波恩近似和L-J相互作用势,建立了原子—双原子分子碰撞系统转动传能的量子干涉模型,描述了观察和测量微分干涉角的方法,得到了微分干涉角与碰撞半径和碰撞速度间的关系,同时也得到了积分干涉角和实验温度的关系.此理论模型对于理解和进行分子束实验是非常重要的.     

The differential interference angle in collisional quantum interference on rotational energy transfer

Collisional quantum interference （CQI） in the intramolecular rotational energy transfer was observed in experiment by Sha and co-workers. The interference angle, which measuring the degree of the coherence, were measured in the experiment of the static cell. Based on the first Born approximation of time dependent perturbation theory, taking into accounts the anisotropic Lennard-Jones interaction potentials, this paper describes the theoretical model of CQI in intramolecular rotational energy transfer in an atom-diatom collision system. In the model, the differential interference angle for the experiment of the molecular beam is calculated, the changing tendencies of the differential interference angle with the impact parameter and collision partners are obtained. This theoretical model is important for understanding or performing this kind of experiments.     

量子干涉效应中干涉角和散射角的研究

利用波恩近似理论对双原子激发态转动传能进行了剖析,更深入的研究了原子分子碰撞过程中量子干涉效应相关信息．利用各项异性相互作用势和直线轨迹近似建立了新的量子干涉模型,讨论了原子与分子碰撞时散射角和微分干涉角的关系,得到了干涉角和各向异性参数及转动量子数的关系．     

Na2(A1∑u+,v=8～b3Ⅱ0u,v=14)-Na体系转动传能的碰撞量子干涉效应

沙国河及其工作组于1995年发表了CO A1Π(v=0)～e3∑-(v=1)与He1,Ne及其它碰撞伴的碰撞过程中转动传能的碰撞量子干涉现象,并得到了积分干涉角,陈等从理论和实验上发现了Na2(A1∑u ,v=8～b3Π0u,v=14)体系与Na(3s)碰撞的碰撞量子干涉现象,孙等计算了其积分干涉角,但是对微分干涉角没有过多的计算.本文作为对原子-双原子体系碰撞诱导转动传能的进一步理论研究,在含时一级波恩近似的基础上考虑各向异性相互作用势和长程相互作用势,计算了单叁混合态的Na2(A1∑u ,v=8-bΠ0u,v=14)体系与Na碰撞的微分干涉角,并得到了微分干涉角与碰撞参数的关系,此理论模型对理解和进行分子束实验是非常重要的.     

The differential interference angle of ^2∏[Case（a）] diatom on rotational energy transfer in NO（X^2∏） collision with He,Ne and Ar system

To study theoretically the relationship between the differential interference angle and the scattering angle in collisional quantum interference （CQI）, we have investigated the differential interference angle of the atom-diatomic [case（a）] molecule system in detail. For the 2∏ electronic state in Hund＇s case （a）, the degree of the differential interference is also discussed. The differential interference angles of NO（X^2∏） are calculated quantitatively for the rotational energy transfer in Hund＇s case （a） induced by collision with He, Ne and Ar atoms. The method to calculate the differential interference angle is presented. Several factors that affect the differential interference angle are investigated. Finally the variation of the differential interference angle with the impact parameter and relative velocity is discussed.     

Na_2(A~1∑_u~+,v=8～b~3∏_(0u),v=14)-Na体系转动传能的碰撞量子干涉效应(英文)

沙国河及其工作组于1995年发表了COA^1∏（v=0）～e^3∑^-（v=1）与He,Ne及其它碰撞伴的碰撞过程中转动传能的碰撞量子干涉现象,并得到了积分干涉角,陈等从理论和实验上发现了Na2（A^1∑u^＋,v=8～b^3∏0u,v=14）体系与Na（3s）碰撞的碰撞量子干涉现象,孙等计算了其积分干涉角,但是对微分干涉角没有过多的计算.本文作为对原子-双原子体系碰撞诱导转动传能的进一步理论研究,在含时一级波恩近似的基础上考虑各向异性相互作用势和长程相互作用势,计算了单叁混合态的Na2（A^1∑u^＋,v=8～b^3∏0u,v=14）体系与Na碰撞的微分干涉角,并得到了微分干涉角与碰撞参数的关系,此理论模型对理解和进行分子束实验是非常重要的.     

Interference Angle on Quantum Rotational Energy Transfer in Na+Na2 (A1 Σ+u,v=8∽ b3 Π0u,v=14) Molecular Collision System

In order to study the collisional quantum interference (CQI) on rotational energy transfer in atom-diatom system, we have studied the relation of the integral interference angle and differential interference angle in Na+Na₂ (A¹Σ^+_u, v=8∽b³Π_0u, v=14) collision system. In this paper, based on the first-Born approximation of time-dependent perturbation theory and takinginto accounts the anisotropic effect of Lennard-Jones interaction potentials,we present a theoretical model of collisional quantum interference inintramolecular rotational energy transfer, and a relationship betweendifferential and integral interference angles.     

单三重混合态Na2(A1∑+u,ν=8～b'3Ⅱ0u,ν=14)和Na碰撞传能的干涉相位角的计角

文章详细介绍了单三重混合态同核双原子分子Na2(A1∑+u,ν=8～b'3Ⅱ0u,ν=14)和Na碰撞传能的干涉相位角的理论计算方法.并且采用了两种不同的相互作用势(一种是长程吸引相互作用势,另一种是Lennard-Jones相互作用势),进行了具体的数值计算.在实验温度750 K下,计算积分干涉相位角,与实验值相差很小.干涉相位角的大小表明混合态体系碰撞传能中的量子干涉效应是不容忽视的.最后,分析了干涉相位角随着不同参数的变化关系,发现Na2 Na体系中,干涉相位角随各参数变化而变化,但变化不大.     

双向剪切干涉法测量高斯光束远场发散角

对双向剪切干涉理论和高斯光束传输特性进行了研究.提出了一种测量高斯光束远场发散角的方法：利用双向剪切干涉仪分别在激光传输路径上两个特定位置测出波前曲率半径,然后由曲率半径得出发散角.通过理论推导建立了相应的检测模型,并对模型进行了实验验证.实验测量和误差分析表明该方法的测量准确度能达到10″;发散角测量准确度的主要影响因素为干涉条纹宽度测量误差.     

Collisional Quantum Interference on Rotational Energy Transfer： Relation Between Integral Interference Angle and Rotational Quantum Number in Na2（A^1∑u^＋,ν=8～b^3∏0u,ν=14）-Na System

Collisional quantum interference （CQI） on rotational energy transfer was observed in Na2（A^1∑u^＋,ν=8～b^3∏0u,ν=14） system in collision with Na [Chem. Phys. Lett. 318 （2000） 107], and the degree of the interference was measured. The integral interference angle was obtaJned through theoretical calculation. We will research the factors that have effect on collisional quantum interference on rotational energy transfer in Na2（A^1∑u^＋,ν=8～b^3∏0u,ν=14）-Na system. Basing on the time-dependent first order Born approximation, and taking into account the anlsotroplc Lennard Jones interaction potentials and ＂straight-line＂ trajectory approximation, we obtain the factors that have effect on CQI in Na2-Na system, and obtain the relation between the integral interference angle and rotational quantum number.     

偏振型干涉成像光谱仪中Savart偏光镜通光孔径的研究

论述了偏振型干涉成像光谱仪的核心部件——Savart偏光镜的结构和分光机理. 应用波法线追迹的方法, 对光在任意方位入射面内, 以任意入射角入射时Savart偏光镜中的光线传播规律及出射光孔径变化进行了理论推导, 给出了出射孔径与入射位置、入射角及入射方位角之间满足的关系, 并讨论了光线传播始终处于Savart偏光镜晶体内部, 最终从出射面射出所需满足的条件. 采用计算机模拟, 给出了光线垂直入射时, 出射孔径的表达式, 验证了推导的正确性; 在此基础上对自行设计的干涉成像光谱仪通光孔径进行了详细分析和讨论, 结果表明通光孔径精确值和近似值之间存在较大差异. 给出了孔径面积利用率随入射方位角的变化曲线, 阐明在干涉成像光谱仪的参数论证以及孔径光阑的选取中, 不能忽略由于晶体双折射现象带来的孔径变化. 研究结果可为偏振型干涉成像光谱仪的设计、研制、调试和工程化提供重要的理论依据和实践指导.     

AB(~1∏,J)+C(~(s_1)l_(1j_1))→AB(~1∏,J′)+C(~(s_1)l_(1j_1)′)+C(~(s_2)l_(2j_2)′)电子和转动传能的电子量子干涉

在我们以前的理论研究中,给出了AB(1∏,J) C(sli)→AB(1∏,J′) C(slj′)碰撞诱导电子和转动传能的理论模型.为了进一步在理论上研究AB(1∏,J) C(s1l1j1)→AB(1∏,J′) C(s1l1j1′) C(s2l2j2′)的电子和转动传能的电子量子干涉,以波恩奥本海默近似为基础,考虑各项异性Lennard-Jones相互作用势,给出了其理论模型.得出了衡量干涉程度的干涉角,对完全干涉的情况进行了讨论,得出了决定几率比的因素,此理论模型对理解和进行这种类型的实验是很重要的.     

AB(~1∑,J)+C(~(S_1)l_(1i_1))→AB(~1∑,J′)+C(~(S_1)l_((1j_1)′))+C(~(S_2)l_((2j_2)′))中电子传能与转动传能的量子干涉(英文)

本文为了进一步在理论上对AB(~1∑,J) C(~(S_1)l_(1i_1))→AB(~1∑,J′) C(~(S_1)l_((1j_1)′)) C(~(S_2)l_((2j_2)′))的转动传能量子干涉进行研究,提出了理论模型,此模型对理解和进行实验是非常重要的.在含时一级波恩近似的基础上,考虑各向异性相互作用势,推导出衡量干涉程度的干涉角,并讨论完全干涉的情况,得到影响几率比的因素.     

AB(1∑,J)+C(S1l1i1)→AB(1∑,J'')+C(S1l1j1'')+C(S2l2j2'')中电子传能与转动传能的量子干涉

本文为了进一步在理论上对AB(1∑,J)+C(S1l1i1)→AB(1∑,J')+C(S1l1j1')+C(S2l2j2')的转动传能量子干涉进行研究,提出了理论模型,此模型对理解争进行实验是非常重要的.在舍时一级波恩近似的基础上.考虑各向异性相互作用势,推导出衡量干涉程度的干涉角,并讨论完全干涉的情况,得到影响几率比的因素.     

Eikonal approximation for single-electron capture from hydrogen molecules by proton impact

A four-body eikonal approximation is developed to study the single-electron capture process in collision of the fast protons with the hydrogen molecular targets. For a fixed orientation of the molecular axis, the double-differential cross sections are evaluated for electron capture. Interference patterns originated from the two atomic centres are obtained for different orientations of the molecular target. Equal-weighted average of the differential capture cross sections over all the possible orientations of the molecular target is calculated for various impact energies. Angular distributions of the differential cross sections for single charge transfer at various impact energies as a function of the angle between the axis of the molecule and the incident beam direction are calculated and compared with their corresponding experimental values as well as the results obtained from other theories. Integrated cross sections are calculated and compared with available experimental data and other theoretical calculations.     

The frequency shifting of laser light by electro-optic techniques

In velocity measurements by the laser Doppler method, a requirement exists for changing the frequency of one light beam with respect to another derived from the same source. This is particularly useful for the determination of the sign of a velocity. The required frequency shifting or single side-band generation can be accomplished by the use of electro-optical effects and a number of possible arrangements are discussed. Trials were made using Kerr cells and electro-optic crystals and single side-band generation demonstrated by a simple Doppler beating experiment. If a low efficiency can be tolerated as in Doppler beating with a reference beam, the production of a pure frequency shifted beam is not difficult up to frequencies of a few megahertz. The differential Doppler or fringe system however requires shifted and non-shifted beams of equal intensity and hence high efficiency conversion is imperative. Radio-frequency driving power requirements may also be a limitation. The theoretical efficiencies of various multi-cell electro-optic arrangements have been calculated as a function of R.F. excitation. The possible efficiency approaches unity as the number of cells is increased.     

用双光束干涉制作二维光子晶体

利用双光束干涉,在光敏材料上制作光子晶体结构.通过改变两束光之间的夹角可以改变制备样品的周期.改变曝光次数以及两次曝光时干涉条纹的夹角可以分别得到一维、二维正方晶格以及二维三角晶格结构的光子晶体.