Structure of D Pair in Collective States of Nuclei

As a successive work a modified D pair independent of the S pair treated in our previous papers is introduced to avoid the seniority mixing problem. The structure amplitudes of this D pair and S pair are determined simultaneously and self-consistently by iteration.     

The Structure of S Pair in Collective States (Ⅰ)

A new S pair and seniority particle operator used to overcome the difficulties due to seniority mixing are defined in collective motion of nuclei. The structure amplitude of S pair is determined in a self-consistent manner.     

Operat orized Bogoliubov Transformat ion and Seniority Mixing in Collective States of Nuclei

The operatorized Bogoliubov transformation (OBT) to deal with the seniority mixing problem in the cojlective states composed of S and D nucleon pairs is introduced. The spurious components of such states due to seniority mixing are disdussed and evaluated by using OBT.     

锕系核集体运动的负宇称态

从锕系区40多个核的正负宇称态的实验数据,如激发能、J^π、电偶极跃迁等,得到一系列与核结构有关的物理量,如宇称劈裂能级差δE_I,正负宇称带的第一和第二类转动惯量J⁽¹⁾和J⁽²⁾及第一负宇称态的电偶极跃迁强度比等,以及它们与角动量I或转动角频率ω的动力学和核子数A的系统行为,从而为研究锕系核负宇称态的产生机制及动力学特点提供了信息.     

Pair Excitations in Even-Even Nuclei

A charge exchange term is added to the n-p effective interaction in treating eveneven nuclei with shape coexistence. The energy spectra and some of the E2 transition rates are calculated for ^112,114Cd, ^114,116Sn and ^118,120Te nuclei. The inclusion of this new term helps to improve an agreement with experimental data.     

动态关联和110Cd的集体态

提出了动态关联的概念,并用这种关联讨论了¹¹⁰Cd的集体态. 同时还考虑了该核素中的g玻色子自由度,并在sdf玻色子的框架下讨论了它的八极态.     

q变形对相干态及其反聚束效应

利用q变形玻色产生算符和湮没算符及其逆算符的性质，引入了q变形的两种对相干态，研究了q变形对相干态的反聚束效应和两模间的关联特性. 结果表明，q变形对相干态呈现反聚束效应，两模的光子相互关联，并且q参数对这些非经典特性的调节比较明显，随着q偏离1越大，这些特性越明显.     

q变形对相干态的相位概率分布特性

通过推广Pegg和Barnett的相位算符和相位态到q变形的双模情况, 应用数值计算 研究了q变形对相干态的相位概率分布特性. 结果表明, q变形对相干态的相位概率分布受到相位参数、q参数和参数│ξ│的调节, 从而反映出不同的量子相干特性.     

Quasiprobability Distribution Functions of Squeezed Pair Coherent States

Using the entangled state representation of Wigner operator and some formulae related to the two-variable Hermite polynomials, the Wigner function of the squeezed pair coherent state (SPCS) and its two marginal distributions are derived. Based on the entangled Husimi operator introduced by Fan et al. (Phys. Lett. A 358:203, 2006) and the Weyl ordering invariance under similar transformations, we also obtain the Husimi function of the SPCS and its marginal distribution functions. The comparison between the two quasibability functions shows that, for the same amount of information included in two functions, the solving process of the Husimi function is simpler than that of the Wigner function. Work supported by the Natural Science Foundation of Shandong Province of China under Grant Y2008A23 and the Natural Science Foundation of Liaocheng University under Grant X071049.     

轴对称变形核中配对粒子态的构成

量子多粒子体系的配对粒子态的构成与体系对称性密切相关.轴对称变形核中的配对粒子态可有三种构成方式,即单极对,±Ω和Signature对,分别是(J2,J3),J3,和(J32,R1(π))的共同本征态.在只计及对力时,三种形式的对力得出的能谱完全相同,常被等价地混用.但在推转壳模型中,由于三种配对态在空间转动下的性质不尽相同,能谱及有关性质随ω的变化将有不同程度的差异.     

奇偶对相干态的维格纳函数和层析图函数

利用纠缠态η〉表象下的维格纳算符,重构了奇偶对相干态的维格纳函数.根据维格纳函数在相空间中随变量ρ和γ的变化规律,讨论了奇偶对相干态的非经典性质和量子干涉效应.研究发现,奇偶对相干态总呈现非经典性质,并且当q取奇数时,奇偶对相干态更容易出现非经典性质.奇偶对相干态的量子干涉效应的显著程度与q取值有关,但对于q的同一取值,奇对相干态的量子干涉效应更为显著.利用纠缠态η〉表象下的维格纳算符Δ1,2(ρ,γ)和纠缠态η,τ1,τ2〉的投影算符之间满足的拉东变换,获得了奇偶对相干态的量子层析图函数.     

集体运动态中的辛弱数混合

在由S和D核子关联对构成的原子核集体运动态中,存在由辛弱数混合造成的伪态成份. 给出了计算这种伪态成份的公式,并进行计算和讨论.     

24Mg集体态的三体非对角玻色相互作用修正

引入三体非对角玻色相互作用计算了²⁴Mg的能谱,克服了以往理论谱中0过低的困难,改进了理论和实验的符合程度.说明在某些情形下三体非对角玻色相互作用有可能是重要的.     

Entanglement and Teleportation of Pair Cat States in Amplitude Decoherence Channel

The dynamic behavior of the entanglement for the pair cat states in the amplitude decoherence channel is studied by adopting the entanglement of formation determined by the concurrence. Then, we consider the teleportation by using joint measurements of the photon-number sum and phase difference with the pair cat states as an entangle resource and discuss the influence of amplitude decoherence on the mean fidelity of the teleportation.     

Entanglement and Teleportation of Pair Cat States in Amplitude Decoherence Channel

The dynamic behavior of the entanglement for the pair cat states in the amplitude decoherence channel is studied by adopting the entanglement of formation determined by the concurrence. Then, we consider the teleportation by using joint measurements of the photon-number sum and phase difference with the pair cat states as an entangle resource and discuss the influence of amplitude decoherence on the mean fidelity of the teleportation.     

Generation of SU（2） Coherent States for a Cavity Mode and a Collective Atomic Mode

We propose a scheme for generation of SU（2） coherent states for an atomic ensemble and a cavity mode. In the scheme a collection of two-level atoms resonantly interact with a single-mode quantized field. Under certain conditions, the system can evolve from a Fock state to a highly entangled SU（2） coherent state. The operation speed increases as the number of atoms increases, which is important in view of deeoherence.     

非线性孪相干态的光子统计性质

利用f振子的湮没算符和产生算符的逆算符的性质，得到了SU(1，1)李代数的两个双模非厄密实现，在此基础上引入了两种非线性孪相干态，并讨论了它们的光子统计性质和相位特性。     

Correlated Nucleon Pair Model and Microscopic Basis of Interacting Boson

An earlier work dealing with low-lying collective states in nuclei is revised and improved. Correlated and independent nucleon S and D pairs properly modified so that they behave approximately like bosons are constructed in terms of which a model space for lowlying collective states is defined, and a microscopic basis for IBM is thus set up. All dynamical variables can also be "bosonized", i.e., expressed in terms of these "bosons" but with statedependent coefficients or operators to incorporate their state dependence in model space.     

Simplified Scheme for Teleportation of a Multipartite Quantum State Using a Single Entangled Pair

Abstract A simple scheme for teleporting an unknown M-qubit cat-like state is proposed. The steps of this scheme can be summarized simply： disentangle-teleport-reconstruct entanglement. If proper unitary operations and measurements from senders are given, the teleportation of an unknown M-qubit cat-like state can be converted into single qubit teleportation. In the meantime, the receiver should also carry out right unitary operations with the introduction of appropriate ancillary qubits to confirm the successful teleportation of the demanded entangled state. The present scheme can be generalized to teleport an unknown M-quNit state, i.e., an M-quNit state can be teleported by a single quNit entangled pair.