Experimental architecture of joint remote state preparation

Motivated by some previous joint remote preparation schemes, we first propose some quantum circuits and photon circuits that two senders jointly prepare an arbitrary one-qubit state to a remote receiver via GHZ state. Then, by constructing KAK decomposition of some transformation in SO(4), one quantum circuit is constructed for jointly preparing an arbitrary two-qubit state to the remote receiver. Furthermore, some deterministic schemes of jointly preparing one-qubit and two-qubit states are presented. Besides, the proposed schemes are extended to multi-sender and the partially entangled quantum resources.     

Efficient joint remote preparation of an arbitrary two-qubit state via cluster and cluster-type states

In this paper, we present a possible improvement of the successful probability of joint remote state preparation via cluster states following some ideals from probabilistic joint remote state preparation (Wang et al. in Opt Commun, 284:5835, 2011). The success probability can be improved from $1/4$ to 1 via the same quantum entangled channel by adding some classical information and performing some unitary operations. Moreover, we also discussed the scheme for joint remote preparation via cluster-type states. Compared with other schemes, our schemes have the advantage of having high successful probability for joint preparation of an arbitrary two-qubit state via cluster states and cluster-type states.     

Perfect joint remote state preparation of arbitrary six-qubit cluster-type states

In this paper, a joint remote state preparation protocol, which is applicable to six-qubit cluster states, is presented. The scheme is performed with the help of three quantum channels constituted by eight qubits. A new index of efficiency for JRSP protocols is defined. A comparison is made with the existing similar schemes from which it is concluded that the present scheme utilizes its resources more efficiently. The work is a part of the line of research on transfer and remote preparation of entanglement.     

Classical communication cost and probabilistic remote two-qubit state preparation via POVM and W-type states

I present a new scheme for probabilistic remote preparation of a general two-qubit state by using two W-type states as the shared quantum channel and a proper POVM instead of the usual positive measurement. Also I explore the scheme??s applications to five special ensembles of two-qubit states. The success probability and the classical communication cost in different cases are calculated minutely, respectively, which show that the remote two-qubit preparation can be realized with higher probability after consuming some more classical bits provided that the two-qubit state to be prepared is chosen from the special ensembles.     

Deterministic joint remote preparation of arbitrary two- and three-qubit entangled states

We present several schemes for joint remote preparation of arbitrary two- and three-qubit entangled states with complex coefficients via two and three GHZ states as the quantum channel, respectively. In these schemes, two senders (or N senders) share the original state which they wish to help the receiver to remotely prepare. To complete the JRSP schemes, some novel sets of mutually orthogonal basis vectors are introduced. It is shown that, only if two senders (or N senders) collaborate with each other, and perform projective measurements under suitable measuring basis on their own qubits, respectively, the receiver can reconstruct the original state by means of some appropriate unitary operations. The advantage of the present schemes is that the success probability in all the considered JRSP can reach 1.     

Joint remote preparation of four-qubit cluster-type states with multiparty

For N+1-sender independently share the classical knowledge of a quantum state, a new scheme for joint remote preparation of four-particle cluster-type states using only two partially two-particle entangled states as quantum channel is presented. In our scheme, each of the senders is just required to perform a bipartite projective measurement, and the receiver adopts some appropriate unitary operation to obtain the original state with certain probability. We also discuss four type information-splitting methods which can make the receiver obtain the unknown state. The classical communication cost is also calculated.     

Joint remote preparation of arbitrary two- and three-photon state with linear-optical elements

Quantum Information Processing - In this paper, two schemes for joint remote preparation via linear optics elements are proposed. Firstly, we propose a scheme for joint remote preparation of an...     

Three-party remote state preparation schemes based on entanglement

By exploiting the entanglement correlation in quantum mechanics, two three-party remote state preparation (RSP) schemes are proposed. One is three-party remote preparation of a single-particle quantum state, and the other is three-party remote preparation of a two-particle entangled state. In the proposed schemes, the sender Alice knows the quantum states to be prepared, while the receivers Bob and Charlie do not know the quantum states; Alice performs measurement and unitary operations on her own particles with two three-particle GHZ states as the quantum channel. According to Alice’s measurement results, Bob and Charlie measure their own particles on the corresponding quantum measurement bases and perform unitary operations on the corresponding particles to reconstruct the quantum states, respectively. Compared with multiparty joint remote preparation and two-party RSP of a quantum state, the proposed schemes realize quantum multicast communication successfully, which enables Bob and Charlie to obtain the prepared quantum states simultaneously in the case of just knowing Alice’s measurement results, while Bob and Charlie do not know each other’s prepared quantum states. It is shown that only three classical bits are required for the two proposed RSP schemes when Bob and Alice introduce an auxiliary particle, respectively, and the proposed schemes are secure after the quantum channel authentication.     

Deterministic remote preparation via the Brown state

We propose two deterministic remote state preparation (DRSP) schemes by using the Brown state as the entangled channel. Firstly, the remote preparation of an arbitrary two-qubit state is considered. It is worth mentioning that the construction of measurement bases plays a key role in our scheme. Then, the remote preparation of an arbitrary three-qubit state is investigated. The proposed schemes can be extended to controlled remote state preparation (CRSP) with unit success probabilities. At variance with the existing CRSP schemes via the Brown state, the derived schemes have no restriction on the coefficients, while the success probabilities can reach 100%. It means the success probabilities are greatly improved. Moreover, we pay attention to the DRSP in noisy environments under two important decoherence models, the amplitude-damping noise and phase-damping noise.     

Controlled remote state preparation protocols via AKLT states

In this paper, we proposed two controlled remote state preparation of an arbitrary single-qubit state schemes one for deterministic controlled remote state preparation the other for probabilistic controlled-joint remote state preparation with 2/3 probability. Both of them used the Affleck–Kennedy–Lieb–Tasaki (AKLT) state which consisted of bulk spin-1’s and two spin-1 \(/\) 2’s at the ends. Up to now, no RSP protocols using AKLT gapped ground states as a shared quantum resource had been presented thus far and Fan et al. showed the other AKLT property was that if we performed a Bell measurement on bulk, then a maximally entangled state would be shared by two ends. We utilized these properties to develop our controlled protocols.     

Deterministic remote two-qubit state preparation in dissipative environments

We propose a new scheme for efficient remote preparation of an arbitrary two-qubit state, introducing two auxiliary qubits and using two Einstein–Podolsky–Rosen (EPR) states as the quantum channel in a non-recursive way. At variance with all existing schemes, our scheme accomplishes deterministic remote state preparation (RSP) with only one sender and the simplest entangled resource (say, EPR pairs). We construct the corresponding quantum logic circuit using a unitary matrix decomposition procedure and analytically obtain the average fidelity of the deterministic RSP process for dissipative environments. Our studies show that, while the average fidelity gradually decreases to a stable value without any revival in the Markovian regime, it decreases to the same stable value with a dampened revival amplitude in the non-Markovian regime. We also find that the average fidelity’s approximate maximal value can be preserved for a long time if the non-Markovian and the detuning conditions are satisfied simultaneously.     

Two efficient schemes for probabilistic remote state preparation and the combination of both schemes

We propose two novel schemes for probabilistic remote preparation of an arbitrary quantum state with the aid of the introduction of auxiliary particles and appropriate local unitary operations. The first new proposal could be used to improve the total successful probability of the remote preparation of a general quantum state, and the successful probability is twice as much as the one of the preceding schemes. Meanwhile, one can make use of the second proposal to realize the remote state preparation when the information of the partially entangled state is only available for the sender. This is in contrast to the fact that the receiver must know the non-maximally entangled state in previous typical schemes. Hence, our second proposal could enlarge the applied range of probabilistic remote state preparation. Additionally, we will illustrate how to combine these novel proposals in detail, and our results show that the union has the advantages of both schemes. Of course, our protocols are implemented at the cost of the increased complexity of the practical realizations.     

The faithful remote preparation of general quantum states

This paper is to establish a theoretical framework for faithful and deterministic remote state preparation, which is related to the classical Hurwitz theorem. And then based on the new theory various schemes with different characteristics are presented. Moreover, the permutation group and the partially quantum resources have also discussed for faithful schemes.     

Multiparty-controlled joint remote state preparation

In this work, we present a novel and efficient information-processing way, multiparty-controlled joint remote state preparation (MCJRSP), to transmit quantum information from many senders to one distant receiver via the control of many agents in a network. We firstly put forward a scheme regarding MCJRSP for an arbitrary single-particle state via Greenberg–Horne–Zeilinger entangled states, and then extend to generalize an arbitrary two-particle state scenario. Notably, different from conventional joint remote state preparation, the desired states cannot be recovered but all of agents collaborate together. Besides, both successful probability and classical information cost are worked out, the relations between success probability and the employed entanglement are revealed, the case of many-particle states is generalized briefly, and the experimental feasibility of our schemes is analysed via an all-optical framework at last. And we argue that our proposal might be of importance to long-distance communication in prospective quantum networks.     

A highly efficient scheme for joint remote preparation of multi-qubit W state with minimum quantum resource

We present a highly efficient scheme for perfect joint remote preparation of an arbitrary \( 2^{n} \)-qubit W state with minimum quantum resource. Both the senders Alice and Bob intend to jointly prepare one \( 2^{n} \)-qubit W state for the remote receiver Charlie. In the beginning, they help the remote receiver Charlie to construct one n-qubit intermediate state which is closely related to the target \( 2^{n} \)-qubit W state. Afterward, Charlie introduces auxiliary qubits and applies appropriate operations to obtain the target \( 2^{n} \)-qubit W state. Compared with previous schemes, our scheme requires minimum quantum resource and least amount of classical communication. Moreover, our scheme has a significant potential for being adapted to remote state preparation of other special states.     

Multiple independent quantum states sharing under collaboration of agents in quantum networks

This paper presents a systematic approach for implementing arbitrary unknown multi-qubit state sharing by multiple agents and its generalization to independent state joint sharing collaborated with multi control agents in quantum deterministic and probabilistic networks. To supervise all independent processes of quantum state sharing, each control agent needs to hold and measure only one particle. This scheme can be used in multi-layer quantum networks to monitor the data flow in secured communication. The performance analysis shows that less qubit resources and less amount of classical communication information are required compared with existing schemes.     

一种基于SSM的多源组播路由协议

为满足参与方同时为收发方的组播通信模式,该文提出了一种新的基于特定源组播的多源组播路由协议SSM-MSM,该协议利用特定源组播形成的单向组播转发树维护一个与之并行的用于多方通信的双向转发树,其路由状态、树建立和控制消息开销和组播包转发时延较小,可综合几种已有的基于SSM多方通信方案的优势。     

Quantum operation sharing with symmetric and asymmetric W states

Two tripartite schemes for sharing a single-qubit operation on a remote target state are proposed with symmetric and asymmetric W states, respectively. They 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 first scheme is better than the second one. In particular, the sharing can be achieved probabilistically with the first scheme while deterministically with the second one.     

任意二粒子纠缠态的受控量子通信

为了解决任意二量子通信问题,首先给出了五粒子和七粒子纠缠态的构造方法,并提供了它们的量子线路图。其次,以该五粒子纠缠态为量子信道,提出一个任意二粒子未知量子态的受控隐形传态协议。该协议在监察者Charlie的控制下,Alice进行四粒子投影测量和经典通信,Bob采用简单酉变换就能以100%的概率成功重构一个任意二粒子纠缠态。最后,利用七粒子纠缠态为量子信道,提出了任意二粒子纠缠态的联合受控远程制备方案。在此方案中,发送者Alice用自己掌握被制备态的部分信息构造测量基,发送者Bob采用前馈测量策略,接收者Diana在监控者Charlie的帮助下,通过简单幺正变换就能确定性地恢复原始态。     

Remote preparation of an arbitrary multi-qubit state via two-qubit entangled states

We propose a novel scheme for remote preparation of an arbitrary n-qubit state with the aid of an appropriate local \(2^n\times 2^n\) unitary operation and n maximally entangled two-qubit states. The analytical expression of local unitary operation, which is constructed in the form of iterative process, is presented for the preparation of n-qubit state in detail. We obtain the total successful probabilities of the scheme in the general and special cases, respectively. The feasibility of our scheme in preparing remotely multi-qubit states is explicitly demonstrated by theoretical studies and concrete examples, and our results show that the novel proposal could enlarge the applied range of remote state preparation.