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1.
本文利用时间切片离子速度成像技术对AlO分子在193 nm下的光解反应动力学进行了研究. 实验通过产物Al+的离子速度和角度分布分析,发现了两个光解离反应通道,分别为中性AlO分子的单光子解离生成产物Al(2Pu)+O(3Pg)的通道,和AlO分子吸收两个光子电离产生AlO+进而解离生成产物为Al+(1Sg)+O(3Pg)的反应通道. 每一个解离通道包括了AlO(v=0∽2)振动态的贡献,其中中性解离反应通道与离子解离反应通道相比,产物的各向异性参数对AlO的振动态依赖更大.  相似文献   

2.
在193 nm的单色激光实验中,本文利用时间切片离子速度成像技术,研究了经193 nm双光子电离得到的Si2+的解离反应动力学过程. 根据实验得到的Si+离子的速度成像,观测到了两种离子直接解离通道:Si(3Pg)+Si+(2Pu)和Si(1D2)+Si+(2Pu). 电子基态的Si2分子处于v=0∽5的振动态上,其经过双光子电离后激发到Si2+离子的多个电子激发态势能面,生成主要通道Si(3Pg)+Si+(2Pu),其中v=1的解离信号最强. 此外,由于势能曲线22Πg与32Πg相同对称性引起的避免性势能面交叉,生成次要反应通道Si(1D2)+Si+(2Pu). 通道Si(1D2)+Si+(2Pu)的产物亦可以由生成的基态Si2+(X4Σg-)吸收一个193 nm光子后解离得到,其对应产物则具有更大的动能.  相似文献   

3.
本文利用时间切片离子成像技术对OCS分子进行了真空紫外波段的光解动力学研究. 在四个光解光波长(从129.32到126.08 nm)下测量了硫原子解离产物S(3PJ=2,1,0)、S(1D2)、S(1S0)的速度影像,并从中清晰地发现了四个主要的解离产物通道:S(3PJ=2,1,0)+CO(X1Σ+),S(3PJ=2,1,0)+CO(A3π),S(1D2)+CO(X1Σ+)和S(1S0)+CO(X1Σ+). 在实验影像中,产物CO分子的部分振动态结构能够得到分辨. 实验还获取解离产物总平动能谱,产物分支比和角分布. 对实验结果进行分析显示除绝热解离通道S(3PJ=2,1,0)+CO(A3π)之外,在其他三个产物通道中非绝热效应都起到非常重要的作用.  相似文献   

4.
本文利用两束可调谐真空紫外激光和离子速度成像的方法测量了CO在108000∽113200 cm-1光解离通道分支比[C(3P0)+O(1D)]/{[C(3P0)+O(3P)]+[C(3P0)+O(1D)]}和[C(3P2)+O(1D)]/{[C(3P2)+O(3P)]+[C(3P2)+O(1D)]}. 本文先用一束真空紫外激光将CO分子激发至特定的高激发量子态并发生解离,接着用另一束真空外激光选择性地电离C(3P0)和C(3P2)并进行探测. 1VUV+1UV/visible共振增强多光子电离的方法大大提高了实验的探测灵敏度,使得之前没有观测到的较弱的吸收带也首次被观测到. 通过分支比的测量,发现自旋禁阻的解离通道C(3P0)+O(1D)和C(3P2)+O(1D) 只在某些分立的较窄能量范围内才能被观测到. 这可能是由于直接激发的高里德堡态和解离到上述自旋禁阻通道的价态在这些能量范围内发生了共振的自旋-轨道耦合相互作用.  相似文献   

5.
本文利用可调谐真空紫外光源和时间切片离子速度成像技术研究了OCS分子的真空紫外光解动力学. 在对应OCS里德堡F态的五个光解波长下(133.26 nm∽139.96 nm)实验采集了S(3PJ=2,1,0)产物的离子影像,从中发现了两个解离通道:S(3PJ=2,1,0)+CO(X1Σ+)和S(3PJ=2,1,0)+CO(A3π),其中前者为主要通道. 离子影像中CO产物的振动结构可部分分辨. 从离子影像中提取出了S(3PJ=2,1,0)+CO(X1Σ+)通道的产物总平动能分布、各向异性参数和CO振动态分支比等信息. 发现了对应OCS在F态的几个低振动态下光解的产物各向异性参数取负值,而对应F态的几个高振动态下光解产物的各向异性参数为正值. 另外,同一光解波长下三种S产物S(3P2)、S(3P1)和S(3P0)的各向异性参数也不相同. 经分析,这些现象可能来源于激发区域的其它不同对称性的电子态的贡献,从而导致解离过程中同时存在平行解离和垂直解离. 本工作有利于进一步理解OCS真空紫外光解中的非绝热耦合作用.  相似文献   

6.
利用光外差-浓度调制吸收光谱技术测量了b3Πg~a3u+(9,3)带在12065~12445 cm-1的光谱,并研究了He2分子b3Πg(v=9)态与c3g+ 态的预解离相互作用.基于He2分子c3g+ 态的ab initio理论计算势能曲线和b3Πg态的RKR势能曲线,分析了b3Πg(v=9)态的预解离机制,并计算了b3Πg(v=9)态转动能级的预解离线宽,计算结果同实验测量基本一致.  相似文献   

7.
本文用时间切片离子速度影像技术研究CS2分子在204 nm附近的光解离动力学. 在201.36、203.10、204.85和206.61 nm这四个解离波长下,实验清楚地观测到S(3PJ)+CS(X1Σ+)产物通道. 在实验获得的S(3PJ=2,1,0)影像中,对应的CS(X1Σ+)产物的振动态结构得到了部分的分辨. 通过对影像的分析,还获得了解离的总平动能谱以及产物的各项异性参数. 实验观察到的相对小的各项异性参数表明产物更倾向于经历了间接的光解离过程. 这一通道的自旋-轨道禁阻特征也说明了非绝热效应在二硫化碳紫外光解离生成S(3PJ=2,1,0)+CS(X1Σ+)的过程中发挥了重要作用.  相似文献   

8.
本文利用时间切片离子速度成像技术在134∽140 nm波段研究了OCS分子经由F 31Π里德堡态的真空紫外光解离动力学. 在选取的5个分别对应OCS(F 31Π, v1=0∽4)的伸缩振动激发的光解波长,实验测得了来自CO(X1Σ+)+S(1D2)产物通道的SS(1D2))实验影像,并获得了总平动能谱和CO(X1Σ+, v)共生产物的振动布居及角分布. 结果分析表明OCS分子解离生成CO(X1Σ+)+S(1D2)产物的过程经历了上态F 31Π 与C?v和Cs构型的下电子态间非绝热耦合过程. 实验结果显示了很强的波长相关性:OCS (F 31Π, v1)的较低转动激发态(v1=0∽2)和较高转动激发态(v1=3, 4)的CO(X1Σ+)产物的振动布居和角分布具有显著差异,表明该解离过程中具有不同的解离机理. 本结果提供了振动耦合可能对真空紫外光解离动力学产生关键作用的相关证据.  相似文献   

9.
本文通过时间切片离子速度成像技术在201 nm附近研究了HNCO分子在S1电子激发态的光解动力学. CO产物通过共振增强多光子电离的方法进行了选态探测,获得了CO产物的振动基态和激发态切片影像. 从CO的影像得到了解离产物的能量分布和空间角分布,确定了NH(a1Δ)产物的振转态分布信息. 研究发现1NH的振动分支比(v=1/v=0)随CO(v=0)转动能的增大先增大后下降,展现了1NH与CO之间特殊的态态相关性. 大约一半的可资用能分配给解离产物的平动自由度. 负的各向异性参数表明HNCO的光解是个快速的直接解离过程.  相似文献   

10.
利用"时间切片"离子速度成像技术研究了N2O分子在134.20、135.20和136.43 nm波长下的真空紫外光解动力学. 实验中通过采集解离产物O(1SJ=0)的离子影像来研究O(1SJ=0)+N2(X1g+)这一解离通道. 从各个波长下的实验影像可获得产物N2(X1g+)的振动态分辨的结构,进而得到产物的总平动能谱和产物N2的振动态布居. 实验结果表明在实验的光解波长下,产物N2(X1g+)主要布居在v=2和v=3. 此外,还得到了产物N2的振动态分辨的各向异性参数β,从中发现产物N2β值在三个解离波长下均表现出相似的特征,即随着振动量子数的增大,β值从趋近于2逐渐减小至1.4. 这一现象表明低振动态产物是通过一个以平行跃迁解离为主的解离过程产生的,而高振动态的产物来自于一个更加弯曲的中间构型的解离. 此推论与在平动能谱中所见到的最强转动态布居随着振动量子数的增大而出现的位移是相一致的.  相似文献   

11.
王珍  王志玺 《中国物理 B》2008,17(8):2790-2794
This paper obtains an entangled condition for isotropic-like states by using an atomic map. It constructs a class of bound entangled states from the entangled condition and shows that the partial transposition of the state from the constructed bound entangled class is an edge bound entangled state by using range criterion.  相似文献   

12.
A scheme is suggested for the generation of multi-atom maximally entangled states with a cavity in a thermalstate. In this scheme several appropriately prepared two-level atoms are simultaneously sent through the nonresonantcavity. We divide the whole atom-cavity interaction time into two equal parts. At the end of the first part a π pulse isapplied to the atoms using a classical field. Then the photon-number-dependent shifts on the atomic states are cancelledand the atomic system finally evolves to a maximally entangled state.  相似文献   

13.
In this paper, we introduce two new classes of nonlinear squeezed states that we name as f-deformed squeezed vacuum state|ξ, f even and f-deformed squeezed first excited state |ξ, f odd, which according to their production processes, essentially include only even and odd bases of Fock space, respectively. In the continuation, we introduce the superposition of these two distinct nonlinear squeezed states with a respective phase ?. Then, some of the criteria which imply the nonclassicality of the states, such as Mandel parameter, second-order correlation function, quadrature squeezing, amplitude-squared squeezing, Husimi and Wigner–Weyl quasi-distribution functions, are numerically examined. At last, by considering a well-known nonlinearity function associated with a nonlinear physical system, we present our results which outcome from the numerical calculations. It is shown that, the introduced f-deformed states can reveal high nonclassical features.  相似文献   

14.
刘翔 《中国物理 C》2010,34(9):1405-1407
In my talk,we present the dynamical study of Y(4140) and Y(3930) under the D*s D*s and D* D* molecular assignments respectively.The importance to theoretically and experimentally study their open-charm decay,hidden-charm decay,radiative decay and double-photon decay is proposed combing with the theoretical calculation of the decay behavior of Y(4140) and Y(3930).According to the recent new experimental progress made by Belle,we further indicate the reasonability of molecular explanation to Y(4140).Another event cluster around 4270 MeV in the J/ψφ invariant mass spectrum of B → KJ/ψφ can provide us more hints to reveal the creation mechanism of molecular structure in B meson decay,which will be helpful to clarify the underlying structure of Y(4140) and Y(3930).  相似文献   

15.
In my talk,we present the dynamical study of Y(4140)and Y(3930)under the D*s(D)*s and D*(D)*molecular assignments respectively.The importance to theoretically and experimentally study their open-charm decay,hidden-charm decay,radiative decay and double-photon decay is proposed combing with the theoretical calculation of the decay behavior of Y(4140)and Y(3930).According to the recent new experimental progress made by Belle,we further indicate the reasonability of molecular explanation to Y(4140).Another event cluster around 4270 MeV in the J/ψφ invariant mass spectrum of B → KJ/ψφ can provide us more hints to reveal the creation mechanism of molecular structure in B meson decay,which will be helpful to clarify the underlying structure of Y(4140)and Y(3930).  相似文献   

16.
A scheme is suggested for the generation of multi-atom maximally entangled states with a cavity in a thermal state,In this scheme several appropriately prepared two-level atoms are simultaneously sent through the nonresonant cavity.We divide the whole atom-cavity interaction time into two equal parts.At the end of the first part a π pulse is applied to the atome using a classical field.Then the photon-number-dependent shifts on the atomic states are cancelled and the atomic system finally evoloves to a maximally entangled state.  相似文献   

17.
能量公设与热力学系统独立状态参量的选取   总被引:6,自引:2,他引:4  
论述了能量公设,并得到能量状态的一般表达式由各种能位形式组成,每一种能位形式可表示为一个强度量和一个广延量的乘积.由此,提出了热力学系统独立状态参量的数目由能位数目来决定,并且每一个独立状态参量只能是组成同一能位的强度量ξi和广延量ξi中的一个.  相似文献   

18.
In this paper, using an exponential function of intensity of radiation field, two new classes of nonlinear coherent states will be constructed. For the first class, we choose the nonlinearity function as fβ(n) = exp(βn), where β characterizes the strength of the nonlinearity of the quantum system. We show that, the corresponding β-states possess a collection of non-classicality features, only for the particular values of β and z. But, interestingly there exists finite (threshold) values of β, for which all of the non-classicality signs will disappear, in appropriate regions around the origin of the complex plane (z < |Z|). It is then illustrated that, using this threshold (or greater) value of β, the corresponding β-states behave very similar to canonical coherent states, as the most classical quantum states, in approximately whole of the space. In the continuation, we motivate to find another class of nonlinear coherent states, limited to a unit disk centered at the origin, looking like the canonical coherent states in behavior, in exactly the whole range of |z| < 1. This purpose also will be achieved by considering the nonlinearity function as , where λ is a tunable nonlinearity parameter. The canonical coherent state's aspects of the corresponding λ-states will be refreshed, in particular cases, working with a threshold (or greater) value of λ.  相似文献   

19.
李家华  杨文星  彭菊村 《中国物理》2004,13(10):1700-1706
In this paper, we present a scheme for preparation of multicomponent motional coherent and squeezed coherent states of the quantized centre of mass of an ion trapped in a one-dimensional harmonic potential and driven by two travelling-wave laser beams tuned to the nth red and blue vibrational sidebands, respectively. In addition, our scheme also provides experimental possibility for quantum state engineering.  相似文献   

20.
张爱林 《中国物理 C》2007,31(8):792-796
介绍了多夸克态的研究现状. 主要介绍了四夸克态、五夸克态和双重子态的理论研究. 并列举了实验上观察到的可能是多夸克态的粒子或共振态.  相似文献   

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