Classical Communication Help and Probabilistic Teleportation with One-Dimensional Non-maximally Entangled Cluster States

We present an explicit protocol for probabilistic teleport an arbitrary and unknown two-qubit entangled state via a one-dimensional four-particle non-maximally entangled cluster state. By construction, our four-partite state is not reducible to a pair of Bell states. We show that teleportation can be successfully realized with a certain probability. This protocol indicate that the four-qubit state is a likely candidate for the genuine four-particle analogue to a Bell state.     

通过四个纠缠态粒子来实现未知的三个纠缠态粒子的量子几率隐形传输

提出一种分别利用四个三态粒子的最大纠缠态和非最大纠缠态作为量子通道来传输一未知的三个三态粒子纠缠态的方案.首先考察量子通道是最大纠缠态的情况,然后进一步考察量子通道是非最大纠缠态的情况,同时发现在后者情况时,通过引进一个辅助粒子,并构造一幺正变换矩阵,即可以一定的几率完成该三态粒子纠缠态的隐形传输.     

基于五粒子团簇态实现经济和简单的二粒子任意态的可控隐形传态(英文)

通过对五粒子团簇态新应用的研究,提出了一个经济和简单的二粒子任意态的可控隐形传态方案.在这个方案中,发送者(Alice)、控制者(Charlie)和接收者(Bob)共享一个五粒子团簇态,发送者只需要执行Bell基测量,而控制者也仅需要执行单粒子投影测量.接受者根据发送者和控制者的测量结果,对自己拥有的粒子做适当的幺正变换,就可以重建发送者的二粒子任意态.这个可控隐形传态方案是决定性的,成功的概率为100%.与使用相同的量子信道进行二粒子任意态的可控隐形传送方案相比,不需要执行多粒子的联合测量,从而使得这个方案更加简单.     

二粒子部分纠缠未知态的量子受控传递

提出了二粒子部分纠缠态的量子隐形传递控制方案.在该方案中,以四个二能级粒子GHZ态作为量子通道,把量子通道中的一个粒子作为控制粒子.在传递者和控制者进行一系列的量子操作和测量之后,根据他们的测量结果,接收者再进行适当的变换就能得到待传递粒子的量子态.     

Quantum Secure Direct Communication Using Six-Particle Maximally Entangled States and Teleportation

The sender shares six-particle maximally entangled states as quantum channel with the receiver. If the quantum channel is secure, the sender performs projective measurements and tells the measurement outcome to the receiver. The receiver performs the unitary transformations and makes projective measurements on his particles to obtain the secret information. Using teleportation, the transmission of three-qubit secret information can be completed in each quantum channel     

基于四粒子GHZ态的可控量子双向隐形传态及安全性

提出一个基于四粒子GHZ纠缠态实现未知单粒子态的可控量子双向传态方案.通信双方Alice和Bob以及控制方事先密享两对四粒子GHZ纠缠态以构建量子信道,根据纠缠粒子的不同分发方式,以及测量时所选择的不同测量基,可以分别实现三方和四方参与的可控量子双向传态.通信开始后,Alice和Bob分别对自己拥有的部分粒子作量子投影测量,若控制方同意双方通信,则对自己拥有的粒子作测量并通过经典信道公布测量结果.通信双方根据控制方公布的测量结果对各自的某个粒子作相应的幺正变换,即可在己方的粒子上重建对方待传的量子态.由于第三方Charlie以及第四方Dennis的加入,整个双向传态的安全性大为提高.     

Controlled Teleportation Using Four-Particle Cluster State

A controlled teleportation scheme is presented. In this scheme, quantum information of a single-qubit state or an entangled two-qubits state is transmitted from a sender （Alice） to a receiver （Charlie） via a four-particle cluster state under the control of the supervisor （Bob）. The feature of this scheme is that the teleportation between the sender and the receiver depends on the control of the supervisor.     

Controlled Teleportation of an Unknown N-qubit Entangled GHZ State

A scheme for controlled teleportation of an unknown N-qubit entangled GHZ state from the sender Alice to the distant receiver Bob is proposed. And m-qubit GHZ state is sufficient for the task of control by m spatially- separated supervisors. Conditioned on the local operations executed by all participants, Bob can faithfully restore the original state by performing relevant unitary transformations with the aid of some classical message about measurement results. Anyone＇s absence will absolutely lead to the failure of teleportation.     

Scheme for Teleportation of Unknown Entangled Atomic States via Cavity Decay

We present a physical scheme to teleport an unknown atomic entangled state via cavity decay. In the teleportation process, four-particle Greenberger-Horne-Zeilinger （GHZ） state is used as quantum channel, and two unknown entangled atoms and two of four atoms in the four-particle GHZ state are trapped in four leaky cavities, respectively. Based on the joint detection of the photons leak out from the four cavities, we can teleport an unknown entangled state to two other remote atoms with certain probability and high fidelity.     

Scheme for Teleportation of Unknown Entangled Atomic States via Cavity Decay

We present a physical scheme to teleport an unknown atomic entangled state via cavity decay. In the teleportation process, four-particle Greenberger-Horne-Zeilinger (GHZ) state is used as quantum channel, and two unknown entangled atoms and two of four atoms in the four-particle GHZ state are trapped in four leaky cavities,respectively. Based on the joint detection of the photons leak out from the four cavities, we can teleport an unknown entangled state to two other remote atoms with certain probability and high fidelity.     

Controlled Teleportation Using Four-Particle Cluster State

A controlled teleportation scheme is presented. In this scheme, quantum information of a single-qubit state or an entangled two-qubits state is transmitted from a sender (Alice) to a receiver (Charlie) via a four-particle cluster state under the control of the supervisor (Bob). The feature of this scheme is that the teleportation between the sender and the receiver depends on the control of the supervisor.     

二粒子纠缠态受控传递的最佳量子通道

本文研究了如何在二粒子纠缠态的量子受控传递中选择最佳量子通道的问题。分别利用四粒子GHZ态和四粒子特殊"反关联GHZ态"作为量子通道,本文提出了二粒子反关联纠缠态的量子受控传递的两个方案。通过对比两个方案下接受者最后采取的幺正操作的具体矩阵形式,分析了待传量子纠缠态与量子通道的关系,指出了四粒子GHZ态和四粒子特殊"反关联GHZ态"分别是二粒子正关联和反关联纠缠态各自隐形传递应该选择的最佳的量子通道。     

基于五粒子团簇态实现经济和简单的二粒子任意态的可控隐形传态

通过对五粒子团簇态新应用的研究,提出了一个经济和简单的二粒子任意态的可控隐形传态方案.在这个方案中,发送者（Alice）、控制者（Charlie）和接收者（Bob）共享一个五粒子团簇态,发送者只需要执行Bell基测量,而控制者也仅需要执行单粒子投影测量.接受者根据发送者和控制者的测量结果,对自己拥有的粒子做适当的幺正变换,就可以重建发送者的二粒子任意态.这个可控隐形传态方案是决定性的,成功的概率为100%.与使用相同的量子信道进行二粒子任意态的可控隐形传送方案相比,不需要执行多粒子的联合测量,从而使得这个方案更加简单.     

Teleportation of a Kind of Three-Mode Entangled States of Continuous Variables

A quantum teleportation scheme to teleport a kind of tripartite entangled states of continuous variables by using a quantum channel composed of three bipartite entangled states is proposed. The joint Bell measurement is feasible because the bipartite entangled states are complete and the squeezed state has a natural representation in the entangled state basis. The calculation is greatly simplified by using the Schmidt decomposition of the entangled states.     

Teleportation of a Kind of Three-Mode Entangled States of Continuous Variables

A quantum teleportation scheme to teleport a kind of tripartite entangled states of continuous variables by using a quantum channel composed of three bipartite entangled states is proposed. The joint Bell measurement is feasible because the bipartite entangled states are complete and the squeezed state has a natural representation in the entangled state basis. The calculation is greatly simplified by using the Schmidt decomposition of the entangled states.     

Teleportation of Unknown Atomic Entangled States Using GHZ Class States

We propose two physical schemes, which can teleport unknown atomic entangled states from user A （Alice） to user B （Bob） via GHZ class states as quantum channel The two schemes are both based on cavity QED techniques. In the two schemes, teleportation and distillation procedures can be realized simultaneously. The second teleportation scheme is more advantageous than the first one.     

Teleportation of Squeezed Entangled State

Based on the coherent entangled state ｜a, x〉 we introduce the squeezed entangled state （SES）. Then we propose a teleportation protocol for the SES by using Einstein-Podolsky-Rosen entangled state ｜η〉 as a quantum channel. The calculation is greatly simplified by virtue of the Schmidt decompositions of both ｜a, x〉 and ｜η〉. Any bipartite states that can be expanded in terms of ｜a, x〉 may be teleported in this way due to the completeness of ｜a, x〉.     

Probabilistic Teleportation of a Three-Particle GHZ State via Two Three-Particle Entangled W States

A scheme for teleporting an unknown three-particle GHZ state from a sender to either one of two receivers is proposed. In this scheme, the quantum channel is composed of two non-maximally three-particle entangled W states. An unknown three-particle GHZ state can be perfectly teleported probabilistically if the sender performs two generalized Bell-state measurements and the Hadamard operation while either one of two receivers introduces an ancillary particle which is one of the final three particle constituting the teleported state, then performs the controlled-not operation with the ancillary particle as the target bit and introduces an appropriate unitary transformation with the help of the other receiver's simple measurements. All kinds of unitary transformations are given in detail. The present scheme may be directly generalized to teleport an unknown multiparticle GHZ state via two three-particle entangled W states used as the quantum channel.     

一种三粒子一般态的远程控制传送方案

基于七粒子纠缠态信道,提出一种三粒子一般态的远程控制传送方案.发送者进行投影测量后,发布测量结果.在控制者的控制下,接受者根据发送者的测量结果对所在处的粒子进行适当的幺正操作从而重构原始态.此方案可用来实现控制量子通信.     

基于纠缠交换和团簇态实现二粒子任意态的可控隐形传态

提出一个对二粒子任意态的可控隐形传态方案,利用四粒子团簇态作为量子信道,用EPR态实现控制.首先,发送者向控制者提出申请,控制者再对其拥有的2个粒子做Bell基测量,并把结果通知发送者,实现纠缠交换.然后,发送者对自己手中的四个粒子做适当的幺正变换,接着进行纽曼测量,并把结果通知接受者.接受者根据发送者的测量结果,对自己拥有的粒子做适当的幺正变换,就可以重建发送者的二粒子任意态.方案成功的概率为100%.