利用三粒子W态隐形传送三粒子GHZ态

提出一个三粒子GHZ(Greenberger-Horne-Zeilinger)态从发送者传送给两个接收者中任意一个的量子隐形传送方案。此方案用两个三粒子W态作为量子信道。若发送者进行两次贝尔态测量和阿达码门操作,想得到所需传送的三粒子GHZ态的接收者引进一个辅助粒子,进行控制-非操作,同时根据另一个接收者的测量结果实施一个适当的幺正变换操作,可以一定的概率成功地隐形传送三粒子GHZ态。同时,此方案可推广至隐形传送n粒子GHZ态,这时也只需用两个三粒子W态作为量子信道,但这时想得到所需传送的n粒子GHZ态的接收者需引进(n-2)个辅助粒子,进行(n-2)次控制非操作,同时根据另一个接收者的测量结果实施一个适当的幺正变换操作,可以一定的概率成功地隐形传送n粒子GHZ态。     

远程制备三粒子纠缠态

在这篇文章中，主要介绍了用三对最大的和非最大两粒子纠缠态作为量子通道远程制备一个三粒子纠缠态的方案。具体方法与量子隐形传态不同的一点就是：我们事先假定Alice已经知道待被制备的态，而Bob并不知道。然后再通过一系列操作得到我们想要制备的态。最后我们得到一个结论：用远程态制备比量子隐形传态更加节省了经典资源。     

三粒子纠缠相干态的隐形传态

提出了一个利用一个两粒子最大纠缠相干态和一个三粒子纠缠相干态作为量子信道进行三粒子纠缠相干态隐形传态的方案.该方案只需线性光学操作和双模光子数测量.计算结果表明,应用本方案的设置,隐形传态成功的概率与所用的相干态的平均光子数有关,反映了纠缠相干态的非正交特性.     

二粒子部分缠结态的量子隐形传态

利用三粒子的最大缠结态(即GHZ态)作为量子通道,实现二粒子部分缠结态的隐形传态,其成功几率为1.该方案只需借助一个量子比特作为辅助比特和两次贝尔基测量,其操作均为局域操作且在目前技术条件下可以很容易实现.     

利用五粒子簇态实现四粒子态的量子隐形传态

主要研究了运用五粒子簇态作为量子通道来实现特殊形式的四粒子态的量子隐形传态方案.该方案运用了量子力学中量子纠缠的理论.在这个方案中,发送者只需要进行五粒子冯·诺依曼投影测量,接收者根据发送者的测量结果,通过在其量子位上执行一些适当的幺正变换得出原始的四量子比特状态.提出的这个方案可以很好地应对一般的窃听方式.     

利用三粒子W态隐形传送任意三粒子W态

提出一个任意三粒子W态从发送者传送给两个接收者任意一个的量子隐形传送方案.该方案用三个三粒子W态作为量子信道,且有两种方法实现传送目的.若发送者进行三次Bell态测量,想得到所需传送三粒子W态的接收者根据发送者的Bell态测量结果和另一个接收者在计算基{|0>,|1>}下的测量结果实施适当的幺正变换操作,就可以一定概率成功地隐形传送三粒子W态;分析表明如果改变操作秩序,成功实现量子隐形传态的概率不会受到影响.同时,该方案可推广至隐形传送N(N≥4)粒子W态,这时需要用N个三粒子W态作为量子信道.发送者做N次Bell态测量,接收者根据如前所述的所有测量结果实施相应的幺正变换,即可完成对N粒子W态的隐形传送.     

相对论粒子的自旋算符

发展了关于相对论态自旋算符的系统理论.考虑了具有非零静质量的粒子情况.对带自旋的相对论粒子,通常的自旋算符需换为相对论的自旋算符.在Poincar啨群不可约表示的框架里,构造了适用于粒子任意正则态的自旋算符,称为运动自旋.本文的讨论限于量子力学.随后将在量子场论中对此作进一步深入研究.     

利用单个三粒子最大GHZ态或两个EPR态隐形传送任意三粒子GHZ态

提出利用单个三粒子最大Greenberger-Horne-Zeilinger (GHZ)态或两个Einstein-Podolsky-Rosen (EPR)态作为量子信道确定性隐形传送任意三粒子GHZ态的两个方案，并将方案推广至隐形传送任意n(n≥4)粒子GHZ态的情况.讨论了量子信道受噪声影响时隐形传态的保真度.研究发现，当作为量子信道的单个三粒子最大GHZ态受到噪声影响时，隐形传态的保真度仅与量子信道的纠缠度有关，而当作为量子信道的两个EPR态受到噪声影响时，隐形传态的保真度不仅与量子信道的纠缠度有关，还与待传送态的纠缠度有关.所提出的方案具有节省量子信道纠缠资源的特点. 关键词： 隐形传态 三粒子Greenberger-Horne-Zeilinger态 量子逻辑门 保真度     

三粒子纠缠W态隐形传态的正交完备基展开与算符变换

先是对利用单个两粒子及单个三粒子纠缠态作为量子信道实现三粒子纠缠W态的隐形传态方案进行讨论.然后由波函数的叠加原理与算符变换出发,将体系的总量子量按照Bell基展开实现量子隐形传态,给出了变换算符与实际操作算符之间的联系.进一步验证出变换算符可逆是成功实现三粒子纠缠W态隐形传态的必要条件的结论. 关键词： 三粒子纠缠W态 Bell基展开 变换算符 隐形传态     

基于非最大纠缠的五粒子Cluster态的高效量子态共享方案

本文提出了一个新的未知量子态共享方案,使用一个非最大纠缠的五粒子Cluster态作为量子通道来实现任意两粒子未知量子态的共享. 即就是发送方（Alice）,接收方（Bob）和控制方（Charlie）共享一个非最大纠缠的五粒子Cluster态. 与以前传统方案不同,在本方案中发送方引入一个辅助粒子,并对其手中的粒子进行正交完备基测量,而接收方不需要引入辅助粒子,只需要执行适当的幺正操作,即可以方便的完成信息的顺利接收. 控制方通过对自己手中的粒子做单粒子投影测量来控制和协助通信双方,使得任意两粒子的未知量子态共享方案得以成功实现. 关键词： 量子态共享 五粒子Cluster态 正交完备基测量 单粒子投影测量     

TWO-PARTICLE BOUND STATES IN THE QUANTUM SINE-GORDON FIELD THEORY IN (D+1) DIMENSIONS

The two-particle states of the quantum sine-Gordon fields are studied variationally in (D+1) dimensions using the Gaussian wave functional approach. In both (1+1) and (2+1) dimensions, there exist two-particle bound states for certain ranges of coupling constant, where the vacuum states are stable. In the higher dimensions (D > 2), this approximation indicates that the two-particle states may be only the states consisting of two free particles, which is conformable to the triviality of the sine-Gordon field theory previously obtained in recent literatures.     

On quantum solitons and their classical relatives: Bethe Ansatz states in soliton sectors of the sine-Gordon system

Previously we have found that the semiclassical sine-Gordon/Thirring spectrum can be received in the absence of quantum solitons via the spin $\text{1}\text{2}$ approximation of the quantized sine-Gordon system on a lattice. Later on, we have recovered the Hilbert space of quantum soliton states for the sine-Gordon system. In the present paper we present a derivation of the Bethe Ansatz eigenstates for the generalized ice model in this soliton Hilbert space. We demonstrate that via “Wick rotation” of a fundamental parameter of the ice model one arrives at the Bethe Ansatz eigenstates of the quantum sine-Gordon system. The latter is a “local transition matrix” ancestor of the conventional sine-Gordon /Thirring model, as derived by Faddeev et al. within the quantum inverse-scattering method. Our result is essentially based on the N < ∞, Δ = 1, m ? 1 regime. Consequently, the spectrum received, though resembling the semiclassical one, does not coincide with it at all.     

Interaction of kink-lattice solitons with small-amplitude waves in finite-size superlattices

Propagation of large-amplitude electromagnetic fields and their interactions with small-amplitude waves in finite superlattices are considered in the framework of the sine-Gordon theory. Finite-size effects result in modulating the large-amplitude fields to a lattice of kinked waves. This kink-lattice wave displays both a soliton feature and the particle property typical to nonlinear topological excitations. The interaction of the kink-lattice soliton with weak electromagnetic waves reveals an unusual number (exactly three) of bound states, which is attributed to the finite size of the propagation medium.     

Gravity localization in sine-Gordon braneworlds

In this work we study two types of five-dimensional braneworld models given by sine-Gordon potentials. In both scenarios, the thick brane is generated by a real scalar field coupled to gravity. We focus our investigation on the localization of graviton field and the behaviour of the massive spectrum. In particular, we analyse the localization of massive modes by means of a relative probability method in a Quantum Mechanics context. Initially, considering a scalar field sine-Gordon potential, we find a localized state to the graviton at zero mode. However, when we consider a double sine-Gordon potential, the brane structure is changed allowing the existence of massive resonant states. The new results show how the existence of an internal structure can aid in the emergence of massive resonant modes on the brane.     

Critical boundary sine-Gordon revisited

We revisit the exact solution of the two space-time dimensional quantum field theory of a free massless boson with a periodic boundary interaction and self-dual period. We analyze the model by using a mapping to free fermions with a boundary mass term originally suggested in Ref. [J. Polchinski, L. Thorlacius, Phys. Rev. D 50 (1994) 622]. We find that the entire SL (2, C) family of boundary states of a single boson are boundary sine-Gordon states and we derive a simple explicit expression for the boundary state in fermion variables and as a function of sine-Gordon coupling constants. We use this expression to compute the partition function. We observe that the solution of the model has a strong–weak coupling generalization of T-duality. We then examine a class of recently discovered conformal boundary states for compact bosons with radii which are rational numbers times the self-dual radius. These have simple expression in fermion variables. We postulate sine-Gordon-like field theories with discrete gauge symmetries for which they are the appropriate boundary states.     

Dynamics of generalized sine-Gordon soliton in inhomogeneous media

In this paper we introduce a few novel generalized sine-Gordon equations and study the dynamics of its solitons in inhomogeneous media. We consider length, mass, gravitational acceleration and spring stiffness of a coupled pendulums chain as a function of position x. Then in the continuum limit we derive semi-analytical and numerical soliton solutions of the modified sine-Gordon equation in the inhomogeneous media. The obtained results confirm that the behavior of solitons in these media is similar to that of a classical point particle moved in an external potential.     

Critical values of the Yang-Yang functional in the quantum sine-Gordon model

The critical values of the Yang-Yang functional corresponding to the vacuum states of the sine-Gordon QFT in the finite-volume are studied. Two major applications are discussed: (i) generalization of Fendley-Saleur-Zamolodchikov relations to arbitrary values of the sine-Gordon coupling constant, and (ii) connection problem for a certain two-parameter family of solutions of the Painlevé III equation.     

Complete S-matrix of the massive thirring model

On the basis of Zamolodchikov's S-matrix for two sine-Gordon solitons we derive the S-matrix for the scattering of an arbitrary number of particles including bound states.     

NLIE of Dirichlet sine-Gordon model for boundary bound states

We investigate boundary bound states of sine-Gordon model on the finite-size strip with Dirichlet boundary conditions. For the purpose we derive the nonlinear integral equation (NLIE) for the boundary excited states from the Bethe ansatz equation of the inhomogeneous XXZ spin 1/2 chain with boundary imaginary roots discovered by Saleur and Skorik. Taking a large volume (IR) limit we calculate boundary energies, boundary reflection factors and boundary Lüscher corrections and compare with the excited boundary states of the Dirichlet sine-Gordon model first considered by Dorey and Mattsson. We also consider the short distance limit and relate the IR scattering data with that of the UV conformal field theory.     

扭结孤子牛顿动力学行为的奇异摄动理论

利用奇异摄动展开,发展了一种研究sine-Gordon扭结孤子动力学行为的理论,得到了在恒定外力作用下sine-Gordon扭结孤子类似于经典粒子,其运动遵守牛顿运动定律.同时,还得到了它在传播过程中所辐射的色散波的一个形式简单的解析表达式. 关键词： 扭结孤子 奇异摄动展开 动力学行为