Kinetic energy release for the collision-induced dissociation of CO<Superscript>+</Superscript>

The kinetic energy release distributions (KERDs) of C⁺ and O⁺ fragments arising from 5 keV collision-induced dissociation (CID) of CO⁺ ions with helium have been measured. The KERDs of C⁺ and O⁺ exhibit different features corresponding to the states that participate in CID processes. We have identified groups of dissociative and predissociative states, and compare them with theoretical and experimental values.     

Electron-impact dissociation and transient properties of a stored LiH2 - beam

The fragmentation of LiH₂ ^- anions after electron impact was investigated at the heavy-ion storage ring TSR. The main reaction channel was found to be electron detachment followed by a breakup into LiH + H. In the first ms after production of the molecular ions in a cesium sputtering ion source, additional contributions were observed in the Li + H₂ and Li^- + H₂ channels, hinting at an initial population of a short-lived state of the anion. To gain a better understanding of the mechanisms underlying the observed behavior of the system, ab initio calculations of relevant potential energy surfaces were performed at selected geometries. The experimental findings are discussed in the light of these calculations.     

Quantum dynamics of tight-binding networks coherently controlled by external fields

With some reviews on the investigations on the schemes for quantum state transfer based on spin systems, we discuss the quantum dynamics of magnetically-controlled networks for Bloch electrons. The networks are constructed by connecting several tight-binding chains with uniform nearest-neighbor hopping integrals. The external magnetic field and the connecting hopping integrals can be used to control the intrinsic properties of the networks. For several typical networks, rigorous results are shown for some specific values of external magnetic field and the connecting hopping integrals: a complicated network can be reduced into a virtual network, which is a direct sum of some independent chains with uniform nearest-neighbor hopping integrals. These reductions are due to the fermionic statistics and the Aharonov-Bohm effects. In application, we study the quantum dynamics of wave packet motion of Bloch electrons in such networks. For various geometrical configurations, these networks can function as some optical devices, such as beam splitters, switches and interferometers. When the Bloch electrons as Gaussian wave packets input these devices, various quantum coherence phenomena can be observed, e.g., the perfect quantum state transfer without reflection in a Y-shaped beam, the multi-mode entanglers of electron wave by star-shaped network, magnetically controlled switches, and Bloch electron interferometer with the lattice Aharonov-Bohm effects. With these quantum coherent features, the networks are expected to be used as quantum information processors for the fermion system based on the possible engineered solid state systems, such as the array of quantum dots that can be implemented experimentally.      

K2里德堡态新分类

根据里德堡轨道的nl? 特性，对理论计算和实验观察到的钾分子电子态进行了分类．这些态被划分为实贯穿和实非贯穿里德堡态．这种分类更能从本质上解释和预测实验结果．比较了这种分类法对K2的应用和对Na2、Li2的应用．     

岩盐结构氧化锌物态方程的分子动力学模拟

利用分子动力学方法和有效经验对势模型对ZnO岩盐结构高温高压下的物态方程进行了研究， 发现分子动力学方法得到的ZnO岩盐结构的摩尔体积(300?1273 K，3.2?10.4 GPa)和实验结果吻合；另外，基于经验势模型的可靠性预测了1373?2273 K和0? 50 GPa的ZnO岩盐结构的P-V -T关系，并利用相应的热力学公式拟合得到了ZnO岩盐结构常态下的线性热膨胀系数、等温体模量及其对压力的一阶导数等重要的热力学参量．     

对规范粒子极化矢量的一些讨论

对规范粒子的极化矢量做了较为系统的论述. 讨论内容包括极化矢量的具体形式和性质、求和规则和规范传播子之间的关系以及由其张成的投影算子的性质. 通过若干精选的例子, 进一步演示了计算牵涉规范粒子的过程时采用的基本方法和应当注意事项.     

Teleportation of an n-bit one-photon and vacuum entangled GHZ cavity-field state

A scheme for teleporting an arbitrary n-bit one-photon and vacuum entangled Greenberger-Horne-Zeilinger （GHZ） state is proposed. In this scheme, the maximum entanglement GHZ state is used as a quantum channel. We find a method of distinguishing four Bell states just by detecting the atomic states three times, which is irrelevant to the qubit number of the state to be teleported.     

Scheme for entanglement concentration of unknown W class states via linear optics

This paper proposes a scheme for entanglement concentration of unknown triparticle W class states with a certain probability. This protocol is mainly based on the coincidences of single-photon detectors and requires single-photon detectors and linear optical elements. The scheme is feasible within current technology.     

An optical scheme for conditional generation of W state and photon-added coherent state

We propose a simple scheme to generate an arbitrary photon-added coherent state of a travelling optical field by combining an array of degenerate parametric amplifiers and corresponding single-photon detectors. Particularly, when the single-photon-added coherent state is observed by developing the novel technique of Zavatta et al （2004 Science 306 660）, we can simultar/eously obtain the generalized N-qubit W state.     

A controlled quantum teleportation scheme of an N-particle unknown state via three-particle W1 states

In this paper a controlled quantum teleportation scheme of an N-particle unknown state is proposed when N groups of three-particle W1 states are utilized as quantum channels. The quantum information of N-particle unknown state is transmitted from the sender to the recipient under the control of all supervisors. It can be realized with a certain probability. After the sender makes Bell-state measurements and the supervisors perform the computational basis measurements, the recipient will introduce auxiliary particles and carry out unitary transformations depending on classical information from the sender and the supervisors. Finally, the computational basis measurement will be performed by the recipient to confirm whether the teleportation succeeds or not. The successful completion of the scheme relies on all supervisors＇ cooperation. In addition, the fidelity and security of the scheme are discussed.