In the well-known treatment of quantum teleportation, the receiver should convert the state of his EPR particle into the replica of the unknown quantum state by one of four possible unitary transformations. However, t...In the well-known treatment of quantum teleportation, the receiver should convert the state of his EPR particle into the replica of the unknown quantum state by one of four possible unitary transformations. However, the importance of these unitary transformations must be emphasized. We will show in this paper that the receiver cannot transform the state of his particle into an exact replica of the unknown state which the sender wants to transfer if he has not a proper implementation of these unitary transformations. In the procedure of converting state, the inevitable coupling between EPR particle and environment which is needed by the implementation of unitary transformations will reduce the accuracy of the replica.展开更多
The equivalence of multipartite quantum mixed states under local unitary transformations is studied. A criterion for the equivalence of non-degenerate mixed multipartite quantum states under local unitary transformati...The equivalence of multipartite quantum mixed states under local unitary transformations is studied. A criterion for the equivalence of non-degenerate mixed multipartite quantum states under local unitary transformations is presented.展开更多
An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler ...An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler can be considered as an optical field matrix acting on an input light column vector.We investigate the general phase principle of output light image.The complete proof of nonoverlapping-image MMI coupler’s optical unitarity along with the phase analysis of matrix element is provided.Based on a two-dimensional finite-difference time-domain(2 D-FDTD)simulation,the unitary transformation is obtained for a 4×4 nonoverlapping-image MMI coupler within a deviation of 4×10-2 for orthogonal invariance and 8×10-2 for transvection invariance in the C-band spectral range.A compact 1×4 splitter based on cascaded MMI coupler is proposed,showing a phase deviation less than 5.4°while maintaining a low-loss performance in C-band spectra.展开更多
In this paper,we discuss the unitary transformation induced by Z_6 rotations of noncommutative space onthe states |k,q,s〉,which plays a key role in construction for noncommutative solitons T^2/Z_6 by GHS method.As ar...In this paper,we discuss the unitary transformation induced by Z_6 rotations of noncommutative space onthe states |k,q,s〉,which plays a key role in construction for noncommutative solitons T^2/Z_6 by GHS method.As aresult,we prove a well-known 'Gauss Sum' formula in the number theory through a concise way.展开更多
In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuti...In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuting operators. Addressing this issue, a nonstandard unitary transformation technique is highlighted here with new perspective. In a spirit of “quantum” series expansions, the transition probabilities between initial and final states, such as displaced, squeezed and other nonlinearly transformed coherent states are obtained both numerically and analytically. This paper concludes that, although this technique is novel, its implementations for more extended systems are needed.展开更多
To address the issue of low estimation performance of the traditional off-grid sparse Bayesian learning algorithm in the complex shallow-water localization environment for acoustic target direction estimation,this pap...To address the issue of low estimation performance of the traditional off-grid sparse Bayesian learning algorithm in the complex shallow-water localization environment for acoustic target direction estimation,this paper proposes a real-domain out-of-state sparse Bayesian learning algorithm that combines dictionary learning and unitary transformation for direction estimation.The algorithm employs the K-means singular value decomposition dictionary learning method to represent the actual received signal of a uniform linear array using a small number of linear combinations of basic received signals,thereby achieving noise reduction for the original signal.The denoised signal matrix is then constructed into a processing matrix that satisfies the central Hermitian property.By applying a unitary transformation,the signal data is converted from complex-domain operations to real-domain operations,which reduces computational complexity.Finally,singular value decomposition and outlier sparse Bayesian learning algorithms are used for iterative processing to achieve target direction estimation.Simulation analysis and sea trial data results demonstrate that compared with the off-grid sparse Bayesian learning algorithm,under conditions of low signal-to-noise ratio and low frame rate,the proposed algorithm has improved azimuth estimation accuracy and algorithm robustness,and is less complex.展开更多
For applying the perfect code to transmit quantum information over a noise channel,the standard protocol contains four steps:the encoding,the noise channel,the error-correction operation,and the decoding.In present wo...For applying the perfect code to transmit quantum information over a noise channel,the standard protocol contains four steps:the encoding,the noise channel,the error-correction operation,and the decoding.In present work,we show that this protocol can be simplified.The error-correction operation is not necessary if the decoding is realized by the so-called complete unitary transformation.We also offer a quantum circuit,which can correct the arbitrary single-qubit errors.展开更多
We study both classical and quantum relation between two Hamiltonian systems which are mutually connected by time-dependent canonical transformation. One is ordinary conservative system and the other is timedependent ...We study both classical and quantum relation between two Hamiltonian systems which are mutually connected by time-dependent canonical transformation. One is ordinary conservative system and the other is timedependent Hamiltonian system. The quantum unitary operator relevant to classical canonical transformation between the two systems are obtained through rigorous evaluation. With the aid of the unitary operator, we have derived quantum states of the time-dependent Hamiltonian system through transforming the quantum states of the conservative system. The invariant operators of the two systems are presented and the relation between them are addressed. We showed that there exist numerous Hamiltonians, which gives the same classical equation of motion. Though it is impossible to distinguish the systems described by these Hamiltonians within the realm of classical mechanics, they can be distinguishable quantum mechanically.展开更多
A vector potential of a magnetic field in Lagrangian is defined as the necessary partial solution of a inhomogeneous differential equation. The ＂gradient transformation＂ is an addition of arbitrary general solution ...A vector potential of a magnetic field in Lagrangian is defined as the necessary partial solution of a inhomogeneous differential equation. The ＂gradient transformation＂ is an addition of arbitrary general solution of the corresponding homogeneous equation that does not change the Lagrange equations. When dynamics is described by momenta and coordinates, this transformation is not the vector potential modification, which does not change expressions for other physical quantities, but a canonical transformation of momentum, which changes expressions for all fimctions of momentum, not changing the Poisson brackets, and, hence, the integrals of motion. The generating function of this transformation must reverse sign under the time-charge reversal. In quantum mechanics the unitary transformation corresponds to this canonical transformation. It also does not change the commutation relations. The phase of this unitary operator also must reverse sign under the time-charge reversal. Examples of necessary vector potentials for some magnetic fields are presented.展开更多
In order to realize the elevation angle estimation for low-altitude targets at a low computational cost, a generalized multiple signal classification （GMUSIC） algorithm based on unitary transform is proposed, i.e., ...In order to realize the elevation angle estimation for low-altitude targets at a low computational cost, a generalized multiple signal classification （GMUSIC） algorithm based on unitary transform is proposed, i.e., the DU-GMUSlC algorithm. Firstly, the covariance matrix of received data is used to construct the Centro- Hermitian matrix. Then, the real-domain GMUSIC algorithm is used to implement the initial angle estimation, and the multipath attenuation coefficient is calculated in succession. Finally, the attenuation coefficient is taken into account in the GMUSIC method to carry out the secondary angle estimation which is beneficial to further improvement of the angle estimation accuracy. This method can meet requirements of low-angle accuracy as well as lower computational burden. Simulation results prove the correctness and effectiveness of the proposed algorithm. Moreover, field experiment data are used to further validate the effectiveness of this method.展开更多
Optical orbital angular momentum(OAM)mode multiplexing has emerged as a promising technique for boosting communication capacity.However,most existing studies have concentrated on channel(de)-multiplexing,overlooking t...Optical orbital angular momentum(OAM)mode multiplexing has emerged as a promising technique for boosting communication capacity.However,most existing studies have concentrated on channel(de)-multiplexing,overlooking the critical aspect of channel routing.This challenge involves the reallocation of multiplexed OAM modes across both spatial and temporal domains—a vital step for developing versatile communication networks.To address this gap,we introduce a novel approach based on the time evolution of OAM modes,utilizing the orthogonal conversion and diffractive modulation capabilities of unitary transformations.This approach facilitates high-dimensional orthogonal transformations of OAM mode vectors,altering both the propagation direction and the spatial location.Using Fresnel diffraction matrices as unitary operators,it manipulates the spatial locations of light beams during transmission,breaking the propagation invariance and enabling temporal evolution.As a demonstration,we have experimentally implemented the deep routing of four OAM modes within two distinct time sequences.Achieving an average diffraction efficiency above 78.31%,we have successfully deep-routed 4.69 Tbit-s^(-1)quadrature phase-shift keying(QPSK)signals carried by four multiplexed OAM channels,with a bit error rate below 10^(-6).These results underscore the efficacy of our routing strategy and its promising prospects for practical applications.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 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
Utilizing the generalized measurement described by positive operator-wlued measure, this paper comes up with a protocol for teleportation of an unknown multi-particle entangled （GHZ） state with a certain probability...Utilizing the generalized measurement described by positive operator-wlued measure, this paper comes up with a protocol for teleportation of an unknown multi-particle entangled （GHZ） state with a certain probability. The feature of the present protocol is to weaken requirement for the quantum channel initially shared by sender and receiver. All unitary transformations performed by receiver are summarized into a formula. On the other hand, this paper explicitly constructs the efficient quantum circuits for implementing the proposed teleportation by means of universal quantum logic operations in quantum computation.展开更多
We present a scheme for teleporting an unknown arbitrary two-particle state from a sender to either one of two receivers. The quantum channel is composed of two partial entangled three-particle GHZ states. An unknown ...We present a scheme for teleporting an unknown arbitrary two-particle state from a sender to either one of two receivers. The quantum channel is composed of two partial entangled three-particle GHZ states. An unknown arbitrary two-particle state can be perfectly teleported probabilistically if the sender performs two generalized Bell-state measurements and each receiver introduces an appropriate unitary transformation with the help of the other receiver's Hadamard operations and simple measurements.展开更多
A scheme for teleporting a three-particle state is proposed when three pairs of entangled particles are used as quantum channel. After a sender operates the Bell-state measurement, the original state with deterministi...A scheme for teleporting a three-particle state is proposed when three pairs of entangled particles are used as quantum channel. After a sender operates the Bell-state measurement, the original state with deterministic probability can be reconstructed when the receiver performs a corresponding measurement with unitary transformation.展开更多
Two simple schemes for probabilistic teleportation of an arbitrary unknown two-particle state using a non-maximally entangled EPR pair and a non-maximally entangled GHZ state as quantum channels are proposed. After re...Two simple schemes for probabilistic teleportation of an arbitrary unknown two-particle state using a non-maximally entangled EPR pair and a non-maximally entangled GHZ state as quantum channels are proposed. After receiving Alice＇s Bell state measurement results, Bob performs a collective unitary transformation on his inherent particles without introducing the auxiliary qubit. The original state can be probabilistically teleported. Meanwhile, quantum circuits for realization of successful teleportation are also presented.展开更多
This paper proposes a scheme for teleporting a kind of essential three-particle non-symmetric entangled state, which is much more valuable than a GHZ and W state for some applications in quantum information processing...This paper proposes a scheme for teleporting a kind of essential three-particle non-symmetric entangled state, which is much more valuable than a GHZ and W state for some applications in quantum information processing. In comparison with previous proposal of teleportation, the resources of entangled states as quantum channel and the number of classical messages required by our scheme can be cut down. Moreover, it is shown that there exists a class of transformations which ensure the success of this scheme, because the two-particle transformation performed by the receiver in the course of teleportation may be a generic two-particle operation instead of a control-NOT （CNOT） operation. In addition, all kinds of transformations performed by sender and receiver are given in detail.展开更多
We propose a scheme to remotely prepare a general two-particle entangled state by using a bipartite entangled state and a tripartite entangled W state as the quantum channel. Our scheme consists of one sender and two ...We propose a scheme to remotely prepare a general two-particle entangled state by using a bipartite entangled state and a tripartite entangled W state as the quantum channel. Our scheme consists of one sender and two remote receivers. The sender can help either one of the receivers to remotely reconstruct the original state with the assistance of the other receiver＇s single-partlcle orthogona/measurement. We obtain the total success probability and discuss the classical communication cost in our remote state preparation scheme.展开更多
A scheme for controlled teleportation of an arbitrary two-particle state using a maximally entangled EPR pair and a cluster state as the quantum channel is proposed. After receiving Alice＇s Bell state measurement res...A scheme for controlled teleportation of an arbitrary two-particle state using a maximally entangled EPR pair and a cluster state as the quantum channel is proposed. After receiving Alice＇s Bell state measurement results, the controller performs a joint measurement on his particles under a non-maximally entangled Bell-basis. The receiver needs to introduce an auxiliary qubit, and performs a series of appropriate unitary transformations on his particles. The original state can be teleported successfully with the probability 2 cos2θ.展开更多
基金The project supported by National Natural Science Foundation of China under Grant No. 10404037
文摘In the well-known treatment of quantum teleportation, the receiver should convert the state of his EPR particle into the replica of the unknown quantum state by one of four possible unitary transformations. However, the importance of these unitary transformations must be emphasized. We will show in this paper that the receiver cannot transform the state of his particle into an exact replica of the unknown state which the sender wants to transfer if he has not a proper implementation of these unitary transformations. In the procedure of converting state, the inevitable coupling between EPR particle and environment which is needed by the implementation of unitary transformations will reduce the accuracy of the replica.
基金The project supported by the China-Germany Cooperation Project under Grant No. 446 CHV 113/231, ＂Quantum information and related mathematical problems＂ and National Natural Science Foundation of China under Grant Nos. 10375038 and 10271081
文摘The equivalence of multipartite quantum mixed states under local unitary transformations is studied. A criterion for the equivalence of non-degenerate mixed multipartite quantum states under local unitary transformations is presented.
基金Project supported by the National Key Research and Development Program of China(Grant No.2018YFB2200202)the National Natural Science Foundation of China(Grant No.61804148)
文摘An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler can be considered as an optical field matrix acting on an input light column vector.We investigate the general phase principle of output light image.The complete proof of nonoverlapping-image MMI coupler’s optical unitarity along with the phase analysis of matrix element is provided.Based on a two-dimensional finite-difference time-domain(2 D-FDTD)simulation,the unitary transformation is obtained for a 4×4 nonoverlapping-image MMI coupler within a deviation of 4×10-2 for orthogonal invariance and 8×10-2 for transvection invariance in the C-band spectral range.A compact 1×4 splitter based on cascaded MMI coupler is proposed,showing a phase deviation less than 5.4°while maintaining a low-loss performance in C-band spectra.
基金Supported by National Natural Science Foundation of China under Grant No.10575080
文摘In this paper,we discuss the unitary transformation induced by Z_6 rotations of noncommutative space onthe states |k,q,s〉,which plays a key role in construction for noncommutative solitons T^2/Z_6 by GHS method.As aresult,we prove a well-known 'Gauss Sum' formula in the number theory through a concise way.
文摘In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuting operators. Addressing this issue, a nonstandard unitary transformation technique is highlighted here with new perspective. In a spirit of “quantum” series expansions, the transition probabilities between initial and final states, such as displaced, squeezed and other nonlinearly transformed coherent states are obtained both numerically and analytically. This paper concludes that, although this technique is novel, its implementations for more extended systems are needed.
基金supported by the National Natural Science Foundation of China(61761048)the Basic Research Special General project of Yunnan Province(202101AT070132)the Yunnan Minzu University Graduate Research Innovation Fund Project(2024SKY122).
文摘To address the issue of low estimation performance of the traditional off-grid sparse Bayesian learning algorithm in the complex shallow-water localization environment for acoustic target direction estimation,this paper proposes a real-domain out-of-state sparse Bayesian learning algorithm that combines dictionary learning and unitary transformation for direction estimation.The algorithm employs the K-means singular value decomposition dictionary learning method to represent the actual received signal of a uniform linear array using a small number of linear combinations of basic received signals,thereby achieving noise reduction for the original signal.The denoised signal matrix is then constructed into a processing matrix that satisfies the central Hermitian property.By applying a unitary transformation,the signal data is converted from complex-domain operations to real-domain operations,which reduces computational complexity.Finally,singular value decomposition and outlier sparse Bayesian learning algorithms are used for iterative processing to achieve target direction estimation.Simulation analysis and sea trial data results demonstrate that compared with the off-grid sparse Bayesian learning algorithm,under conditions of low signal-to-noise ratio and low frame rate,the proposed algorithm has improved azimuth estimation accuracy and algorithm robustness,and is less complex.
文摘For applying the perfect code to transmit quantum information over a noise channel,the standard protocol contains four steps:the encoding,the noise channel,the error-correction operation,and the decoding.In present work,we show that this protocol can be simplified.The error-correction operation is not necessary if the decoding is realized by the so-called complete unitary transformation.We also offer a quantum circuit,which can correct the arbitrary single-qubit errors.
基金Supported by the Korea Science and Engineering Foundation (KOSEF) Grant Funded by the Korea Government (MOST) under Grant No.F01-2007-000-10075-0
文摘We study both classical and quantum relation between two Hamiltonian systems which are mutually connected by time-dependent canonical transformation. One is ordinary conservative system and the other is timedependent Hamiltonian system. The quantum unitary operator relevant to classical canonical transformation between the two systems are obtained through rigorous evaluation. With the aid of the unitary operator, we have derived quantum states of the time-dependent Hamiltonian system through transforming the quantum states of the conservative system. The invariant operators of the two systems are presented and the relation between them are addressed. We showed that there exist numerous Hamiltonians, which gives the same classical equation of motion. Though it is impossible to distinguish the systems described by these Hamiltonians within the realm of classical mechanics, they can be distinguishable quantum mechanically.
文摘A vector potential of a magnetic field in Lagrangian is defined as the necessary partial solution of a inhomogeneous differential equation. The ＂gradient transformation＂ is an addition of arbitrary general solution of the corresponding homogeneous equation that does not change the Lagrange equations. When dynamics is described by momenta and coordinates, this transformation is not the vector potential modification, which does not change expressions for other physical quantities, but a canonical transformation of momentum, which changes expressions for all fimctions of momentum, not changing the Poisson brackets, and, hence, the integrals of motion. The generating function of this transformation must reverse sign under the time-charge reversal. In quantum mechanics the unitary transformation corresponds to this canonical transformation. It also does not change the commutation relations. The phase of this unitary operator also must reverse sign under the time-charge reversal. Examples of necessary vector potentials for some magnetic fields are presented.
基金supported by the National Natural Science Foundation of China(61101224)the Research on the Altitude Measurement Method for VHF Radar under the Complicated Environment
文摘In order to realize the elevation angle estimation for low-altitude targets at a low computational cost, a generalized multiple signal classification （GMUSIC） algorithm based on unitary transform is proposed, i.e., the DU-GMUSlC algorithm. Firstly, the covariance matrix of received data is used to construct the Centro- Hermitian matrix. Then, the real-domain GMUSIC algorithm is used to implement the initial angle estimation, and the multipath attenuation coefficient is calculated in succession. Finally, the attenuation coefficient is taken into account in the GMUSIC method to carry out the secondary angle estimation which is beneficial to further improvement of the angle estimation accuracy. This method can meet requirements of low-angle accuracy as well as lower computational burden. Simulation results prove the correctness and effectiveness of the proposed algorithm. Moreover, field experiment data are used to further validate the effectiveness of this method.
基金the National Natural Science Foundation of China(62271322)the Guangdong Basic and Applied Basic Research Foundation(2022A1515011003 and 2023A1515030152)the Shenzhen Science and Technology Program(JCYJ20210324095610027 and JCYJ20210324095611030).
文摘Optical orbital angular momentum(OAM)mode multiplexing has emerged as a promising technique for boosting communication capacity.However,most existing studies have concentrated on channel(de)-multiplexing,overlooking the critical aspect of channel routing.This challenge involves the reallocation of multiplexed OAM modes across both spatial and temporal domains—a vital step for developing versatile communication networks.To address this gap,we introduce a novel approach based on the time evolution of OAM modes,utilizing the orthogonal conversion and diffractive modulation capabilities of unitary transformations.This approach facilitates high-dimensional orthogonal transformations of OAM mode vectors,altering both the propagation direction and the spatial location.Using Fresnel diffraction matrices as unitary operators,it manipulates the spatial locations of light beams during transmission,breaking the propagation invariance and enabling temporal evolution.As a demonstration,we have experimentally implemented the deep routing of four OAM modes within two distinct time sequences.Achieving an average diffraction efficiency above 78.31%,we have successfully deep-routed 4.69 Tbit-s^(-1)quadrature phase-shift keying(QPSK)signals carried by four multiplexed OAM channels,with a bit error rate below 10^(-6).These results underscore the efficacy of our routing strategy and its promising prospects for practical applications.
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 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Project supported by the National High Technology Research and Development Program of China(Grant No2006AA01Z419)the Major Research Plan of the National Natural Foundation of China(Grant No90604023)+1 种基金the National Laboratory for Modern Communications Science Foundation of China(Grant No9140C1101010601)the Natural Science Foundation of Beijing(Grant No4072020)
文摘Utilizing the generalized measurement described by positive operator-wlued measure, this paper comes up with a protocol for teleportation of an unknown multi-particle entangled （GHZ） state with a certain probability. The feature of the present protocol is to weaken requirement for the quantum channel initially shared by sender and receiver. All unitary transformations performed by receiver are summarized into a formula. On the other hand, this paper explicitly constructs the efficient quantum circuits for implementing the proposed teleportation by means of universal quantum logic operations in quantum computation.
文摘We present a scheme for teleporting an unknown arbitrary two-particle state from a sender to either one of two receivers. The quantum channel is composed of two partial entangled three-particle GHZ states. An unknown arbitrary two-particle state can be perfectly teleported probabilistically if the sender performs two generalized Bell-state measurements and each receiver introduces an appropriate unitary transformation with the help of the other receiver's Hadamard operations and simple measurements.
文摘A scheme for teleporting a three-particle state is proposed when three pairs of entangled particles are used as quantum channel. After a sender operates the Bell-state measurement, the original state with deterministic probability can be reconstructed when the receiver performs a corresponding measurement with unitary transformation.
基金The project supported by the Natural Science Foundation of Jiangsu Province of China under Grant No. Q1108404
文摘Two simple schemes for probabilistic teleportation of an arbitrary unknown two-particle state using a non-maximally entangled EPR pair and a non-maximally entangled GHZ state as quantum channels are proposed. After receiving Alice＇s Bell state measurement results, Bob performs a collective unitary transformation on his inherent particles without introducing the auxiliary qubit. The original state can be probabilistically teleported. Meanwhile, quantum circuits for realization of successful teleportation are also presented.
基金Project supported by the National Natural Science Foundation of China （Grants No 60373059）, the National Laboratory for Modern Communications Science Foundation of China （Grant No 51436020103DZ4001）, the Major Research Plan of the National Natural Science Foundation of China （Grant No 90604023）, the National Research Foundation for the Doctoral Program of Higher Education of China （Grant No 20040013007）, and the ISN 0pen Foundation.
文摘This paper proposes a scheme for teleporting a kind of essential three-particle non-symmetric entangled state, which is much more valuable than a GHZ and W state for some applications in quantum information processing. In comparison with previous proposal of teleportation, the resources of entangled states as quantum channel and the number of classical messages required by our scheme can be cut down. Moreover, it is shown that there exists a class of transformations which ensure the success of this scheme, because the two-particle transformation performed by the receiver in the course of teleportation may be a generic two-particle operation instead of a control-NOT （CNOT） operation. In addition, all kinds of transformations performed by sender and receiver are given in detail.
基金The project supported by National Natural Science Foundation of China under Grant Nos. 60578050 and 10434060 We would like to thank Dr. Yong-Jian Han and Dr. Zheng-Wei Zhou for their helpful suggestions on the topic of classical communication cost.
文摘We propose a scheme to remotely prepare a general two-particle entangled state by using a bipartite entangled state and a tripartite entangled W state as the quantum channel. Our scheme consists of one sender and two remote receivers. The sender can help either one of the receivers to remotely reconstruct the original state with the assistance of the other receiver＇s single-partlcle orthogona/measurement. We obtain the total success probability and discuss the classical communication cost in our remote state preparation scheme.
基金Supported by the National Natural Science Foundation of China under Grant No. 10774108the Foundation for University Key Young Teacher of Henan Province under Grant No. 2009GGJS-163
文摘A scheme for controlled teleportation of an arbitrary two-particle state using a maximally entangled EPR pair and a cluster state as the quantum channel is proposed. After receiving Alice＇s Bell state measurement results, the controller performs a joint measurement on his particles under a non-maximally entangled Bell-basis. The receiver needs to introduce an auxiliary qubit, and performs a series of appropriate unitary transformations on his particles. The original state can be teleported successfully with the probability 2 cos2θ.
