Deterministic remote state preparation of arbitrary three-qubit state through noisy cluster-GHZ channel

We propose a novel scheme for remote state preparation of an arbitrary three-qubit state with unit success probability, utilizing a nine-qubit cluster-GHZ state without introducing auxiliary qubits. Furthermore, we proceed to investigate the effects of different quantum noises (e.g., amplitude-damping, phase-damping, bit-flip and phase-flip noises) on the systems. The fidelity results of three-qubit target state are presented, which are usually used to illustrate how close the output state is to the target state. To compare the different effects between the four common types of quantum noises, the fidelities under one specific identical target state are also calculated and discussed. It is found that the fidelity of the phase-flip noisy channel drops the fastest through the four types of noisy channels, while the fidelity is found to always maintain at 1 in bit-flip noisy channel.     

High efficient scheme for remote state preparation with cavity QED

In this paper, a scheme is proposed for remote state preparation （RSP） with cavity quantum electrodynamics （QED）. In our scheme, two observers share two-atom nonmaximally entangled state as quantum channels and can realize remote preparation of state of an atom. We also propose a generalization for remote preparation of N-atom entangled state by （N＋1）-atom GHZ-like state （N ≥ 2）. By this scheme, one single-atom projective measurement is enough for the RSP of a qubit or N-atom entangled state, and the probability of success for RSP is unity. Furthermore, we have considered the case where observers use W-like state as quantum channels to realize RSP of a qubit. We compare our scheme with existing ones.     

利用广义Bell态信道联合远程制备一个任意三量子比特态

研究了一个联合远程制备任意三量子比特态的方案。该方案利用广义的Bell态作为量子信道,两个发送者分别选择合适的测量基进行测量,然后利用经典信道把测量结果传送出去,接收者根据测量结果对自己手中的粒子采取适当的幺正操作,然后引入辅助粒子并进行选择性测量,就能概率性的得到想要制备的量子态。研究结果表明:利用不同形式的广义Bell态信道成功实现联合远程制备一个任意三量子比特态的概率是一样的,当量子信道处于最大纠缠态时,可以得到最大的成功概率。     

利用纠缠交换在理想和非理想条件下的远程态制备(英文)

提出了利用纠缠交换技术实现一个纠缠态的远程制备.考虑在量子信道没有遭受噪声影响的条件下,利用一对两粒子纠缠态作为量子信道去实现远程态制备.此外我们考察了噪声存在时的远程态的制备,研究显示不同类型的量子噪声对远程态制备过程的保真度的影响不同.对一个确定量子态,我们考察了消相干效应对其远程制备的影响.     

基于Cluster态和Bell态的任意三粒子态远程制备

本文提出了一个新颖的基于四粒子cluster态和Bell态制备任意三粒子远程制备方案.在发送者(Alice)对自己手中的粒子做正交完备测量,接受者(Bob)对自己手中的粒子做适当的幺正变换后,任意三粒子远程制备成功.对于Alice的两种不同的正交完备基测量的情况,分别计算了远程制备成功的概率.另外,本方案成功制备的概率在一般情况和一些特殊情况下是可以计算的.分析结果表明:在一般情况下,远程态制备可以以1/8的概率实现;但在一些特殊情况下,成功的概率可以提高到1/4、1/2,甚至1.     

基于Cluster态和Bell态的任意三粒子态远程制备(英文)

本文提出了一个新颖的基于四粒子cluster态和Bell态制备任意三粒子远程制备方案.在发送者(Alice)对自己手中的粒子做正交完备测量,接受者(Bob)对自己手中的粒子做适当的幺正变换后,任意三粒子远程制备成功.对于Alice的两种不同的正交完备基测量的情况,分别计算了远程制备成功的概率.另外,本方案成功制备的概率在一般情况和一些特殊情况下是可以计算的.分析结果表明:在一般情况下,远程态制备可以以1/8的概率实现;但在一些特殊情况下,成功的概率可以提高到1/4、1/2,甚至1.     

Trace Distance of Remote State Preparation Through Noisy Channels

In this paper, we study remote state preparation (RSP) by w state through noisy channels. The trace distance is used to describe how close the original state is to the output state. Studies show the trace distance is a function of decohenrence rates and angles of the state to be prepared. At the same time, we investigate the influence of different types of noises on the trace distance and find the various types of noises have different degrees of influence on the trace distance for a definite qubit. We also study changes of the trace distance against polar and azimuthal angles.     

Quantum multicast schemes of different quantum states via non-maximally entangled channels with multiparty involvement

Due to the unavoidable interaction between the quantum channel and its ambient environment, it is difficult to generate and maintain the maximally entanglement. Thus, the research on multiparty information transmission via non-maximally entangled channels is of academic value and general application. Here, we utilize the non-maximally entangled channels to implement two multiparty remote state preparation schemes for transmitting different quantum information from one sender to two receivers synchronously. The first scheme is adopted to transmit two different four-qubit cluster-type entangled states to two receivers with a certain probability. In order to improve success probabilities of such multicast remote state preparation using non-maximally entangled channels, we put forward the second scheme, which deals with the situation that is a synchronous transfer of an arbitrary single-qubit state and an arbitrary two-qubit state from one sender to two receivers. In particular, its success probability can reach 100% in principle, and independent of the entanglement degree of the shared non-maximally entangled channel. Notably, in the second scheme, the auxiliary particle is not required.     

Efficient Polarization Entanglement Distribution for W State Assisted by Frequency Degree of Freedom

We present an efficient faithful polarization entanglement distribution protocol for W state over an arbitrary noise channel,which use the frequency degree of freedom to carry the entanglement during the transmission.We describe the transmission of three-photon W state as an example,and then generalize this scheme to n-qubit W state situation.The remote parties can obtain maximally entangled W states on the polarization of photons,and the success probability is 100% in principle.As there was few entanglement purification for W state,our scheme is an efficient and practical method to share W state entanglement between distant parties,which will be useful in quantum communication.We also show that our scheme can be used to distribute arbitrary multi-particle entangled state.     

概率远程制备多粒子GHZ纠缠态

利用一个(N 1)粒子部分纠缠Greenberger-Home-Zeilinger(GHZ)态作为量子通道,提出了概率远程制备N粒子GHZ态的两个方案.我们考虑了怎样远程制备一个任意的GHZ态,即两个参数α和β都是复数的情况.此外,计算了远程制备总的成功概率和需要的经典信息量.     

Single-Qubit Operation Sharing with Bell and W Product States

Two tripartite schemes are put forward with shared entanglements and Local Operation and Classical Communication (LOCC) for sharing an operation on a remote target sate.The first scheme uses a Bell and a symmetric W states as quantum channels,while the second replaces the symmetric W state by an asymmetric one.Both schemes are treated and compared from the aspects of quantum resource consumption,operation complexity,classical resource consumption,success probability and efficiency.It is found that the latter scheme is better than the former one.Particularly,the sharing can be achieved only probabilistically with the first scheme deterministically with the second one.     

Remote Preparation of an Entangled State in Nonideal Conditions

In this paper, the theoretical investigation of remote preparation of an entangled state is studied in nonideal conditions. Our studies include two parts. In the first part, we consider the remote state preparation (RSP) of an entangled state through two equally noisy quantum channel states, namely, a mixture of Bell states. Studies show there is a particular mixed-state channel for which all pure entangled states remain entangled after this inexact RSP. In the second part, we suppose that noises which quantum channels suffer from can be expressed as the Lindblad operators.The master equation of the system can be expressed in the Lindblad form. Through solving the master equation, we calculate the fidelity as a function of decoherence rates and parameters of the state to be prepared. For a given entangled state, we investigate the influenceof different types of noises on the fidelity.     

Single-Qubit Operation Sharing with Bell and W Product States

Two tripartite schemes are put forward with shared entanglements and Local Operation and Classical Communication (LOCC) for sharing an operation on a remote target sate. The first scheme uses a Bell and a symmetric W states as quantum channels, while the second replaces the symmetric W state by an asymmetric one. Both schemes are treated and compared from the aspects of quantum resource consumption, operation complexity, classical resource consumption, success probability and efficiency. It is found that the latter scheme is better than the former one. Particularly, the sharing can be achieved only probabilistically with the first scheme deterministically with the second one.     

Remote Preparation of an Entangled State in Nonideal Conditions

In this paper, the theoretical investigation of remote preparation of an entangledstate is studied in nonideal conditions. Our studies include two parts. In the first part, we consider the remote state preparation （RSP） of an entangled state through two equally noisy quantum channel states, namely, a mixture of Bell states. Studies show there is a particular mixed-state channel for which all pure entangled states remain entangled after this inexact RSP. In the second part, we suppose that noises which quantum channels suffer from can be expressed as the Lindblad operators. The master equation of the system can be expressed in the Lindblad form. Through solving the master equation, we calculate the fidelity as a function of decoherence rates and parameters of the state to be prepared. For a given entangled state, we investigate the influence of different types of noises on the fidelity.     

Remote preparation of a two-particle state using a four-qubit cluster state

We present a scheme of remote preparation of two-particle states using a particular four-qubit cluster state as the quantum channel. The probability of success regarding this preparation scheme is calculated in both general and some particular cases. Our results show that in general such remote state preparation can be realized with a probability of 1/4. But in several special cases, the probability of success can be improved to 1/2 or even 1.     

Joint remote state preparation of arbitrary two-qubit state with six-qubit state

We present a novelty scheme for joint remote preparation of an arbitrary two-qubit state in a probabilistic manner from a spatially separated multi-sender to one receiver. The probability of success regarding this preparation scheme is calculated in both general and some particular cases. Our results show that in general such remote state preparation can be realized with a probability of 1/4. But in several special cases, the probability of success can be improved to 1/2 or even 1.     

Deterministic joint remote preparation of an arbitrary two-qubit state in the presence of noise

Using two tripartite Greenberger-Horne-Zeilinger （GHZ） states as the shared channels, we investigate the noise effects on the deterministic joint remote preparation of an arbitrary two-qubit state. By unitary matrix decomposition procedure, we first construct the quantum logic circuit of the deterministic joint remote state preparation protocol. Then, we analytically derive the fidelity and the average fidelity for the deterministic joint remote preparation of an arbitrary two- qubit state and of four types of special two-qubit states under the influence of the Pauli noises. It is found that the fidelity depends on the noise types, the qubit-environment coupling strength, and the state to be remotely prepared. Moreover, even if the two GHZ channels are subject to the same environmental noises, the average fidelities for remotely preparing different two-qubit states display different time evolution behaviors. The remote preparation of the identical two-qubit states also shows that the average fidelities affected by different noisy environments exhibit different evolution actions.     

Efficient Multipartite Polarization Entanglement Distribution Over Arbitrary Noise Channel

We present an efficient faithful multipartite polarization entanglement distribution protocol over an arbitrary noisy channel. The spatial degree of freedom is used to carry the entanglement during the transmission. We describe the principle by distributing n-qubit Greenberge-Horne-Zeilinger state and n-qubit W state. Our scheme can be used to distribute arbitrary n-qubit entangled states to n distant locations. The remote parties can obtain maximally entangled states deterministically on the polarization of photons. Only passive linear optics are employed in our setup, which makes our scheme more feasible and efficient for practical application in long distance quantum communication.     

Two Schemes for Probabilistic Remote Preparation of a Four-Particle Entangled Cluster-Type State

Using partial entangled states as the quantum channel, two schemes for probabilistic remote preparation of the four-particle cluster-type state with real and complex coefficients are presented. In the first scheme, the sender and the receiver share two partial Bell states and one partial three-qubit GHZ stats as the quantum channel, and the sender can help a remote receiver to prepare a four-particle entangled cluster-type state by using three-qubit projective measurements with certain probability. In the second scheme, the quantum channel is composed of two partial three-qubit GHZ states, the remote state preparation （RSP） can be successfully realized via the positive operator valued measure （POVM）, and the two-particle projective measurements are also needed in this process. The total success probability and classical communication cost are calculated.     

Self-error-rejecting photonic qubit transmission in polarization-spatial modes with linear optical elements

We present an original self-error-rejecting photonic qubit transmission scheme for both the polarization and spatial states of photon systems transmitted over collective noise channels. In our scheme, we use simple linear-optical elements, including half-wave plates, 50:50 beam splitters, and polarization beam splitters, to convert spatial-polarization modes into different time bins. By using postselection in different time bins, the success probability of obtaining the uncorrupted states approaches 1/4 for single-photon transmission, which is not influenced by the coefficients of noisy channels. Our self-error-rejecting transmission scheme can be generalized to hyperentangled n-photon systems and is useful in practical high-capacity quantum communications with photon systems in two degrees of freedom.