This paper presents a scheme for probabilistic teleportation of an arbitrary GHZ-class state with a pure entangled two-particle quantum channel. The sender Alice first teleports the coefficients of the unknown state t...This paper presents a scheme for probabilistic teleportation of an arbitrary GHZ-class state with a pure entangled two-particle quantum channel. The sender Alice first teleports the coefficients of the unknown state to the receiver Bob, and then Bob reconstructs the state with an auxiliary particle and some unitary operations if the teleportation succeeds. This scheme has the advantage of transmitting much less particles for teleporting an arbitrary GHZ-class state than others. Moreover, it discusses the application of this scheme in quantum state sharing.展开更多
In this paper, two novel schemes for deterministic joint remote state preparation(JRSP) of arbitrary single- and twoqubit states are proposed. A set of ingenious four-particle partially entangled states are construc...In this paper, two novel schemes for deterministic joint remote state preparation(JRSP) of arbitrary single- and twoqubit states are proposed. A set of ingenious four-particle partially entangled states are constructed to serve as the quantum channels. In our schemes, two senders and one receiver are involved. Participants collaborate with each other and perform projective measurements on their own particles under an elaborate measurement basis. Based on their measurement results,the receiver can reestablish the target state by means of appropriate local unitary operations deterministically. Unit success probability can be achieved independent of the channel's entanglement degree.展开更多
Two closest single-qubit states could be diagonalised by the same unitary matrix, which helps to find the relative entropy of entanglement of a two-qubit 'X' state. We formulate two binary equations for the relative...Two closest single-qubit states could be diagonalised by the same unitary matrix, which helps to find the relative entropy of entanglement of a two-qubit 'X' state. We formulate two binary equations for the relative entropy of entanglement and the corresponding closest separable state of a given two-qubit 'X' state. This approach can be applied to get the relative entropy of entanglement of many widely-discussed two-qubit states, such as pure states, Werner states, and so on.展开更多
A scheme for teleporting an arbitrary and unknown three-particle state from a sender to either one of two receivers is proposed. The quantum channel is composed of a two-particle non-maximally entangled state and two ...A scheme for teleporting an arbitrary and unknown three-particle state from a sender to either one of two receivers is proposed. The quantum channel is composed of a two-particle non-maximally entangled state and two three-particle non-maximally entangled W states. An arbitrary three-particle state can be perfectly teleported probabilistically if the sender performs three generalized Bell-state measurements and sends to the two receivers the classical result of these measurements, and either one of the two receivers adopts an appropriate unitary transformation conditioned on the suitable measurement outcomes of the other receiver. All kinds of unitary transformations are given in detail.展开更多
A new representation of an arbitrary and unknown N-particle state is presented at first. As an application, a scheme for teleporting an arbitrary and unknown N-particle state is proposed when N pairs of two-particle n...A new representation of an arbitrary and unknown N-particle state is presented at first. As an application, a scheme for teleporting an arbitrary and unknown N-particle state is proposed when N pairs of two-particle non- maximally entangled states are utilized as quantum channels. After Alice (sender) makes Bell-state measurement on her particles, Bob (recipient) introduces an auxiliary particle and carries out appropriate unitary transformation on his particle and the auxiliary particle depending on classical information from Alice. Then, von Neumann measurement that confirms whether the teleportation succeeds or not is performed by Bob on the auxiliary particle. In order to complete the teleportation, another N-1 times operations need to be performed which are similar to the above ones. It can be successfully realized with a certain probability which is determined by the product of the smaller coefficients of non-maximally entangled pairs. All possible unitary transformations are given in detail.展开更多
A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the origi...A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the original state with deterministic probability can be reconstructed by the receiver when a corresponding unitary transformation is followed.展开更多
The entanglement capacity of two-qubit unitary operator acting on rank two mixed states in concurrence is discussed. The condition of perfect entangler is the same as that acting on pure states and the entanglement ca...The entanglement capacity of two-qubit unitary operator acting on rank two mixed states in concurrence is discussed. The condition of perfect entangler is the same as that acting on pure states and the entanglement capacity is the mixing parameter v1. For non-perfect entangler,the upper and lower bound of the entanglement ca-pacity are given.展开更多
In this paper, the issue of swapping quantum entanglements in two arbitrary biqubit pure states via a local bipartite entangledstate projective measure in the middle node is studied in depth, especially with regard to...In this paper, the issue of swapping quantum entanglements in two arbitrary biqubit pure states via a local bipartite entangledstate projective measure in the middle node is studied in depth, especially with regard to quantitative aspects. Attention is mainly focused on the relation between the measure and the final entanglement obtained via swapping. During the study, the entanglement of formation(EoF) is employed as a quantifier to characterize and quantify the entanglements present in all involved states. All concerned EoFs are expressed analytically; thus, the relation between the final entanglement and the measuring state is established.Through concrete analyses, the measure demands for getting a certain amount of a final entanglement are revealed. It is found that a maximally entangled final state can be obtained from any two given initial entangled states via swapping with a certain probability;however, a peculiar measure should be performed. Moreover, some distinct properties are revealed and analyzed. Such a study will be useful in quantum information processes.展开更多
This paper has proposed a generalized quantum state sharing protocol of an arbitrary two-particle state using non-maximally GHZ states and generalized Bell state measurement.The sender Alice performs two-particle gene...This paper has proposed a generalized quantum state sharing protocol of an arbitrary two-particle state using non-maximally GHZ states and generalized Bell state measurement.The sender Alice performs two-particle generalized Bell state measurements on her two particles in the state sharing process and the controller takes measurements on his particles and transfers the quantum information to the receiver with entanglement swapping by the cooperation of the other agents.It is found that the use of nonmaximally entangled state in quantum state sharing has enabled the secure sharing of the quantum state.展开更多
We present an efcient 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 de...We present an efcient 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 efcient for practical application in long distance quantum communication.展开更多
基金The project supported by National Natural Science Foundation of China under Grant No. 10304022, the Science-Technology Fund of Anhui Province for 0utstanding Youth under Grant No. 06042087, the Key Fund of the Ministry of Education of China under Grant No. 206063, Natural Science Foundation of Hubei Province of China under Grant No, 2006ABA354
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10604008 and 10435020) and Beijing Education Committee (Grant No XK100270454).
文摘This paper presents a scheme for probabilistic teleportation of an arbitrary GHZ-class state with a pure entangled two-particle quantum channel. The sender Alice first teleports the coefficients of the unknown state to the receiver Bob, and then Bob reconstructs the state with an auxiliary particle and some unitary operations if the teleportation succeeds. This scheme has the advantage of transmitting much less particles for teleporting an arbitrary GHZ-class state than others. Moreover, it discusses the application of this scheme in quantum state sharing.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61372076 and 61301171)the 111 Project(Grant No.B08038)the Fundamental Research Funds for the Central Universities,China(Grant No.K5051201021)
文摘In this paper, two novel schemes for deterministic joint remote state preparation(JRSP) of arbitrary single- and twoqubit states are proposed. A set of ingenious four-particle partially entangled states are constructed to serve as the quantum channels. In our schemes, two senders and one receiver are involved. Participants collaborate with each other and perform projective measurements on their own particles under an elaborate measurement basis. Based on their measurement results,the receiver can reestablish the target state by means of appropriate local unitary operations deterministically. Unit success probability can be achieved independent of the channel's entanglement degree.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10804042)supported by the Scientific Research Foundation of the Education Department of Jiangxi Province,China (Project No. GJJ09440)
文摘Two closest single-qubit states could be diagonalised by the same unitary matrix, which helps to find the relative entropy of entanglement of a two-qubit 'X' state. We formulate two binary equations for the relative entropy of entanglement and the corresponding closest separable state of a given two-qubit 'X' state. This approach can be applied to get the relative entropy of entanglement of many widely-discussed two-qubit states, such as pure states, Werner states, and so on.
文摘A scheme for teleporting an arbitrary and unknown three-particle state from a sender to either one of two receivers is proposed. The quantum channel is composed of a two-particle non-maximally entangled state and two three-particle non-maximally entangled W states. An arbitrary three-particle state can be perfectly teleported probabilistically if the sender performs three generalized Bell-state measurements and sends to the two receivers the classical result of these measurements, and either one of the two receivers adopts an appropriate unitary transformation conditioned on the suitable measurement outcomes of the other receiver. All kinds of unitary transformations are given in detail.
文摘A new representation of an arbitrary and unknown N-particle state is presented at first. As an application, a scheme for teleporting an arbitrary and unknown N-particle state is proposed when N pairs of two-particle non- maximally entangled states are utilized as quantum channels. After Alice (sender) makes Bell-state measurement on her particles, Bob (recipient) introduces an auxiliary particle and carries out appropriate unitary transformation on his particle and the auxiliary particle depending on classical information from Alice. Then, von Neumann measurement that confirms whether the teleportation succeeds or not is performed by Bob on the auxiliary particle. In order to complete the teleportation, another N-1 times operations need to be performed which are similar to the above ones. It can be successfully realized with a certain probability which is determined by the product of the smaller coefficients of non-maximally entangled pairs. All possible unitary transformations are given in detail.
文摘A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the original state with deterministic probability can be reconstructed by the receiver when a corresponding unitary transformation is followed.
基金Supported by the National Natural Science Foundation of China (Grant No. 60433050)the Science Foundation of Xuzhou Normal University (Key Project) (Grant No. 06XLA05)
文摘The entanglement capacity of two-qubit unitary operator acting on rank two mixed states in concurrence is discussed. The condition of perfect entangler is the same as that acting on pure states and the entanglement capacity is the mixing parameter v1. For non-perfect entangler,the upper and lower bound of the entanglement ca-pacity are given.
基金supported by the National Natural Science Foundation of China(Grant Nos.11375011 and 11372122)the Natural Science Foundation of Anhui Province(Grant No.1408085MA12)the 211 Project of Anhui University
文摘In this paper, the issue of swapping quantum entanglements in two arbitrary biqubit pure states via a local bipartite entangledstate projective measure in the middle node is studied in depth, especially with regard to quantitative aspects. Attention is mainly focused on the relation between the measure and the final entanglement obtained via swapping. During the study, the entanglement of formation(EoF) is employed as a quantifier to characterize and quantify the entanglements present in all involved states. All concerned EoFs are expressed analytically; thus, the relation between the final entanglement and the measuring state is established.Through concrete analyses, the measure demands for getting a certain amount of a final entanglement are revealed. It is found that a maximally entangled final state can be obtained from any two given initial entangled states via swapping with a certain probability;however, a peculiar measure should be performed. Moreover, some distinct properties are revealed and analyzed. Such a study will be useful in quantum information processes.
基金supported by the National Fundamental Research Program (Grant No.2010CB923202)Chinese Universities Scientific Fund (Grant No.BUPT2009RC0710)+1 种基金Specialized Research Fund for the Doctoral Program of Education Ministry of China (Grant No.20090005120008)the National Natural Science Foundation of China (Grant Nos.10704010 and 10947151)
文摘This paper has proposed a generalized quantum state sharing protocol of an arbitrary two-particle state using non-maximally GHZ states and generalized Bell state measurement.The sender Alice performs two-particle generalized Bell state measurements on her two particles in the state sharing process and the controller takes measurements on his particles and transfers the quantum information to the receiver with entanglement swapping by the cooperation of the other agents.It is found that the use of nonmaximally entangled state in quantum state sharing has enabled the secure sharing of the quantum state.
基金Supported by the National Natural Science Foundation of China under Grant No.11004258Fundamental Research Funds for the Central Universities under Grant No.CQDXWL-2012-014
文摘We present an efcient 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 efcient for practical application in long distance quantum communication.