We propose an efficient method for the generation of perfect W states on three microwave superconducting resonators,of which the two nearest neighbors are coupled by a symmetric direct current superconducting quantum ...We propose an efficient method for the generation of perfect W states on three microwave superconducting resonators,of which the two nearest neighbors are coupled by a symmetric direct current superconducting quantum interference device(dc-SQUID).With suitable external magnetic fluxes applied to the dc-SQUID symmetry loops,on-chip tunable interactions between neighboring resonators can be realized,and different perfect W states can be deterministically created on-demand in one step.Numerical simulations show that high-fidelity target states can be generated and our scheme is robust against imperfect parameter tuning and environment-induced decoherence.The present work may have potential applications for implementing quantum computation and quantum information processing based on microwave photons.展开更多
Multi-hop teleportation has significant value due to long-distance delivery of quantum information. Many studies about multi-hop teleportation are based on Bell pairs, partially entangled pairs or W state. The possibi...Multi-hop teleportation has significant value due to long-distance delivery of quantum information. Many studies about multi-hop teleportation are based on Bell pairs, partially entangled pairs or W state. The possibility of multi-hop teleportation constituted by partially entangled pairs relates to the number of nodes. The possibility of multi-hop teleportation constituted by double W states is (4/9)~n after n-hop teleportation. In this paper, a multi-hop teleportation scheme based on W state and EPR pairs is presented and proved. The successful possibility of quantum information transmitted hop by hop through intermediate nodes is deduced. The possibility of successful transmission is (2/3)~n after n-hop teleportation.展开更多
This paper proposes an alternative scheme for generating four-photon W state via cavity QED. The scheme bases on the resonant interaction of a A-type three level atom with two bimodal cavities. The detection of atom c...This paper proposes an alternative scheme for generating four-photon W state via cavity QED. The scheme bases on the resonant interaction of a A-type three level atom with two bimodal cavities. The detection of atom collapses the cavity to the desired state. Comparing with previous schemes, the advantage of this scheme is that the interaction time can be greatly shortened since it uses the resonant interaction between atom and cavities. Moreover, the proposed scheme is more experimentally feasible than the previous ones.展开更多
Utilizing a three-particle W state, we come up with a protocol for the teleportation of an unknown two-particle entangled state. It is shown that the teleportation can be deterministically and exactly realized. Moreov...Utilizing a three-particle W state, we come up with a protocol for the teleportation of an unknown two-particle entangled state. It is shown that the teleportation can be deterministically and exactly realized. Moreover, two-particle entanglement teleportation is generalized to a system consisting of many particles via a three-particle W state and a multi-particle W state, respectively. All unitary transformations performed by the receiver are given in a concise formula.展开更多
We propose a simple scheme to generate an arbitrary photon-added coherent state of a travelling optical field by combining an array of degenerate parametric amplifiers and corresponding single-photon detectors. Partic...We propose a simple scheme to generate an arbitrary photon-added coherent state of a travelling optical field by combining an array of degenerate parametric amplifiers and corresponding single-photon detectors. Particularly, when the single-photon-added coherent state is observed by developing the novel technique of Zavatta et al (2004 Science 306 660), we can simultar/eously obtain the generalized N-qubit W state.展开更多
We propose a scheme for a fast generating three-qubit W state in a superconducting system by using a technique of shortcuts to adiabaticity, Lewis–Riesenfeld invariants. Three identical superconducting qubits(SQs) ...We propose a scheme for a fast generating three-qubit W state in a superconducting system by using a technique of shortcuts to adiabaticity, Lewis–Riesenfeld invariants. Three identical superconducting qubits(SQs) are connected by two coplanar waveguide resonators(CPWRs) capacitively. Under a certain limit condition, we convert the complicated SQ system into a simple three-state system. By designing experimentally accessible harmonic pulses, a three-SQ W state is implemented with quite short operation time and high fidelity. Numerical simulations prove that the scheme is robust against the parameter deviation. In addition, we also give detailed discussion about the scheme robustness against decoherence.展开更多
In this paper, we accomplish the teleportation of an unknown three-particle maximally entangled W state by using a spin-path entangled quantum channel which may be realized experimentally based on the advanced theory ...In this paper, we accomplish the teleportation of an unknown three-particle maximally entangled W state by using a spin-path entangled quantum channel which may be realized experimentally based on the advanced theory and technique in Bose-Einstein condensate (BEC) of molecule, micro-fabricated wave guide and simple quantum logic gate. Similarly, we can make an arbitrary n-particle entangled Greenberger Horne-Zeilinger (GHZ) state (n ≥ 4) teleported through this kind of quantum channel. It may have important applications due to its resource-economic and practical features.展开更多
The GHZ states and W states are two fundamental types of three qubits quantum entangled states. For finding the knotted pictures of three nodes W states, on the one side, we empty any one node, thus obtaining three de...The GHZ states and W states are two fundamental types of three qubits quantum entangled states. For finding the knotted pictures of three nodes W states, on the one side, we empty any one node, thus obtaining three degenerated twonode W states, then we find the nonzero submatrix of the corresponding covariance correlation tensor in quantum network theory. On the other side, excepting the linkage 41 corresponding to Bell bases, we conjecture that the another one possible oriented link (which is composed of two-component knots entangled with each other and has four crossings) would be the required knotted pictures of the two nodes W states, thence obtain the nonzero submatrix of the Alexander relation matrix in the theory of knot crystals for these knotted pictures. The equality of the two nonzero submatfices of different kinds thus verify the exactness of our conjecture. The superposition of three knotted pictures of two-node W states from different choices of the emptied node gives the knotted pictures of three-node W states, thus shows the correspondence between three-node W states in quantum network theory and the oriented links in knot theory. Finally we point out that there is an intimate and simple relationship between the knotted pictures of GHZ states and W states.展开更多
A scheme is proposed for generating entangled W states with four cavity modes. In this scheme, we send a V-type three-level atom through two identical two-mode cavities in succession. After the atom exits from the sec...A scheme is proposed for generating entangled W states with four cavity modes. In this scheme, we send a V-type three-level atom through two identical two-mode cavities in succession. After the atom exits from the second cavity, the four cavity modes are prepared in the W state. On the other hand we can obtain three-atom W states by sending three V-type three-level atoms through a two-mode cavity in turn. The present scheme does not require conditional measurement, and it is easily generalized to preparing 2n-mode W states and n-atom W states.展开更多
We propose a practical entanglement concentration protocol (ECP) for a hybrid entangled state using quantum dots and a microcavity coupled system. A hybrid less-entangled state can he concentrated to a most-entangle...We propose a practical entanglement concentration protocol (ECP) for a hybrid entangled state using quantum dots and a microcavity coupled system. A hybrid less-entangled state can he concentrated to a most-entangled state with a certain probability using only one ancillary single photon. Moreover, using this protocol, we can also concentrate an arbitrary three-particle less-entangled W state using two ancillary photons and classical communication. The proposed protocols provide us with a useful method to concentrate less-entangled states, which can he implemented with current technology.展开更多
Following the theoretical protocol described by Fortescue and Lo [Fortescue B and Lo H K 2007 Phys. Rev. Lett. 98 2605011, we present a scheme in which one can distill maximally entangled bi-partite states from a tri-...Following the theoretical protocol described by Fortescue and Lo [Fortescue B and Lo H K 2007 Phys. Rev. Lett. 98 2605011, we present a scheme in which one can distill maximally entangled bi-partite states from a tri-partite W state with cavity QED. Our scheme enables the concrete physical system to realize its protocol. In our scheme, the rate distillation also asymptotically approaches one. Based on the present cavity QED techniques, we discuss the experimental feasibility.展开更多
We propose two schemes for generating Greenberger-Horne-Zeilinger and W states of three distant atoms. In the present schemes, the atoms are individually trapped in three spatially separated optical cavities coupled b...We propose two schemes for generating Greenberger-Horne-Zeilinger and W states of three distant atoms. In the present schemes, the atoms are individually trapped in three spatially separated optical cavities coupled by two optical fibres. Performing an adiabatic passage along dark states, the population of cavities and fibres excited is negligible under certain conditions. In addition, the spontaneous decay of atoms is also efficiently suppressed based on our proposals. Furthermore, the discussion about the entanglement fidelity is given and we point out that our schemes work robustly with small fluctuations of experimental parameters.展开更多
The existence of decoherence-free subspace (DFS) has been discussed widely. In this paper, we propose an alternative scheme for generating the four-atom W states by manipulating DF qubits. The atoms are divided into...The existence of decoherence-free subspace (DFS) has been discussed widely. In this paper, we propose an alternative scheme for generating the four-atom W states by manipulating DF qubits. The atoms are divided into two pairs and trapped in two separate optical cavities. Manipulation of atoms within DFS may generate a two-atom maximally entangled state in an individual cavity, which is a stable state. After driving the system out of DFS, the atoms will interact resonantly with the cavity field. The photons leaking from the cavities interfere at the beamsplitter, which destroys which-path information, and are finally detected by one of the detectors, leading to the generation of a W state. In addition, the numerical simulation indicates that the fidelity of the prepared state can, for a very wide parameter regime, be very close to unity.展开更多
In this paper, we investigate perfect quantum teleportation and dense coding by using an 2N-qubit W state channel. In the quantum teleportation scheme, an unknown N-qubit entangled state can be perfectly teleported. O...In this paper, we investigate perfect quantum teleportation and dense coding by using an 2N-qubit W state channel. In the quantum teleportation scheme, an unknown N-qubit entangled state can be perfectly teleported. One ebit of entanglement and two bits of classical communication are consumed in the teleportation process, just like when using the Bell state channel. While N + 1 bits of classical information can be transmitted by only sending N particles in the dense coding protocol.展开更多
A simple scheme is proposed to generate the W state of N A-type neutral atoms trapped in an optical cavity via Raman transition. Conditional on no photon leakage from the cavity, the N-qubit W state can be prepared pe...A simple scheme is proposed to generate the W state of N A-type neutral atoms trapped in an optical cavity via Raman transition. Conditional on no photon leakage from the cavity, the N-qubit W state can be prepared perfectly by turning on a classical coupling field for an appropriate time. Compared with the previous ones, our scheme requires neither individual laser addressing of the atoms, nor demand for controlling N atoms to go through an optical cavity simultaneously with a constant velocity. We investigate the influence of cavity decay using the quantum jump approach and show that the preparation time decreases and the success probability increases with atom number because of a collective enhancement of the coupling.展开更多
Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only relate...Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only related to their coefficients and we successfully apply the general N-qubit W state to quantum state transferand quantum state prepare like that in two-qubit system.展开更多
We propose a scheme to fast prepare the three-qubit W state via superadiabatic-based shortcuts in a circuit quantumelectrodynamics (circuit QED) system. We derive the effective Hamiltonian to suppress the unwanted tra...We propose a scheme to fast prepare the three-qubit W state via superadiabatic-based shortcuts in a circuit quantumelectrodynamics (circuit QED) system. We derive the effective Hamiltonian to suppress the unwanted transitions betweendifferent eigenstates by counterdiabatic driving, and obtain the W state with high-fidelity based on the superadiabaticpassage. The numerical simulation results demonstrate that the proposed scheme can accelerate the evolution, and is moreefficient than that with the adiabatic passage. In addition, the proposed scheme is robust to the decoherence caused by theresonator decay and qubit relaxation, and does not need additional parameters, which could be feasible in experiment.展开更多
Quantum discord is the most prominent of quantum correlations, but it does not have unique generalizations to the multipartite case. W states are especially useful for secure communication. In this paper, we propose t...Quantum discord is the most prominent of quantum correlations, but it does not have unique generalizations to the multipartite case. W states are especially useful for secure communication. In this paper, we propose that the quantum correlation in generic three-qubit pure W states can be given by the two-qubit discords of these states.展开更多
In this paper, two schemes for teleporting an unknown four-particle entangled W state is proposed. In the first scheme, two partial entangled four-particle states are used as quantum channels, while in the second sche...In this paper, two schemes for teleporting an unknown four-particle entangled W state is proposed. In the first scheme, two partial entangled four-particle states are used as quantum channels, while in the second scheme,four non-maximally entangled particle pairs are considered as quantum channels. It is shown that the teleportation can be successfully realized with certain probability, for both schemes, if a receiver adopts some appropriate unitary transformations. It is also shown that the successful probabilities of these two schemes are different.展开更多
A theoretical protocol of quantum dialogue is proposed,which uses a class of three-photon W states asquantum channel.After two-step security check,four-bit secret message can be transmitted to each other by transmitti...A theoretical protocol of quantum dialogue is proposed,which uses a class of three-photon W states asquantum channel.After two-step security check,four-bit secret message can be transmitted to each other by transmittingof single photon with the aid of two-bit classical information.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12174300)the Natural Science Foundation of Hubei Province of China(Grant No.2020CFB748)+2 种基金the Natural Science Foundation of Shandong Province of China(Grant Nos.ZR2021MA042 and ZR2021MA078)the Program for Science and Technology Innovation Team in Colleges of Hubei Province of China(Grant No.T2021012)the Doctoral Scientific Research Foundation of Hubei University of Automotive Technology(Grant Nos.BK202113,BK201906,and BK202008)。
文摘We propose an efficient method for the generation of perfect W states on three microwave superconducting resonators,of which the two nearest neighbors are coupled by a symmetric direct current superconducting quantum interference device(dc-SQUID).With suitable external magnetic fluxes applied to the dc-SQUID symmetry loops,on-chip tunable interactions between neighboring resonators can be realized,and different perfect W states can be deterministically created on-demand in one step.Numerical simulations show that high-fidelity target states can be generated and our scheme is robust against imperfect parameter tuning and environment-induced decoherence.The present work may have potential applications for implementing quantum computation and quantum information processing based on microwave photons.
基金Project supported by the National Natural Science Foundation of China(Grant No.61571105)the Prospective Future Network Project of Jiangsu Province,China(Grant No.BY2013095-1-18)the Independent Project of State Key Laboratory of Millimeter Waves,China(Grant No.Z201504)
文摘Multi-hop teleportation has significant value due to long-distance delivery of quantum information. Many studies about multi-hop teleportation are based on Bell pairs, partially entangled pairs or W state. The possibility of multi-hop teleportation constituted by partially entangled pairs relates to the number of nodes. The possibility of multi-hop teleportation constituted by double W states is (4/9)~n after n-hop teleportation. In this paper, a multi-hop teleportation scheme based on W state and EPR pairs is presented and proved. The successful possibility of quantum information transmitted hop by hop through intermediate nodes is deduced. The possibility of successful transmission is (2/3)~n after n-hop teleportation.
基金supported by National Natural Science Foundation of China (Grant No 10674025)the Development Funds of Fuzhou University of China (Grant No 2007-XY-15)
文摘This paper proposes an alternative scheme for generating four-photon W state via cavity QED. The scheme bases on the resonant interaction of a A-type three level atom with two bimodal cavities. The detection of atom collapses the cavity to the desired state. Comparing with previous schemes, the advantage of this scheme is that the interaction time can be greatly shortened since it uses the resonant interaction between atom and cavities. Moreover, the proposed scheme is more experimentally feasible than the previous ones.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60873191 and 60821001)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 200800131016)+4 种基金the Key Project of Chinese Ministry of Education (Grant No. 109014)the China Postdoctoral Science Foundation Funded Project (Grant No. 20090450018)the Beijing Natural Science Foundation (Grant No. 4072020)the 111 Project (Grant No. B08004)the National Basic Research Program of China (Grant No. 2007CB311203)
文摘Utilizing a three-particle W state, we come up with a protocol for the teleportation of an unknown two-particle entangled state. It is shown that the teleportation can be deterministically and exactly realized. Moreover, two-particle entanglement teleportation is generalized to a system consisting of many particles via a three-particle W state and a multi-particle W state, respectively. All unitary transformations performed by the receiver are given in a concise formula.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10304020 and 10474117), the State Key Development Program for Basic Research of China (Grant No 2001CB309309), and also in part by the Sunshine Project of Wuhan, China.
文摘We propose a simple scheme to generate an arbitrary photon-added coherent state of a travelling optical field by combining an array of degenerate parametric amplifiers and corresponding single-photon detectors. Particularly, when the single-photon-added coherent state is observed by developing the novel technique of Zavatta et al (2004 Science 306 660), we can simultar/eously obtain the generalized N-qubit W state.
基金supported by the National Natural Science Foundation of China(Grant No.11464046)
文摘We propose a scheme for a fast generating three-qubit W state in a superconducting system by using a technique of shortcuts to adiabaticity, Lewis–Riesenfeld invariants. Three identical superconducting qubits(SQs) are connected by two coplanar waveguide resonators(CPWRs) capacitively. Under a certain limit condition, we convert the complicated SQ system into a simple three-state system. By designing experimentally accessible harmonic pulses, a three-SQ W state is implemented with quite short operation time and high fidelity. Numerical simulations prove that the scheme is robust against the parameter deviation. In addition, we also give detailed discussion about the scheme robustness against decoherence.
基金Projects supported by the National Natural Science Foundation of China (Grant No 10374025)the Natural Science Foundation of Hunan Province, China (Grant No 07JJ3013)the Education Ministry of Hunan Province, China (Grant No 06A038)
文摘In this paper, we accomplish the teleportation of an unknown three-particle maximally entangled W state by using a spin-path entangled quantum channel which may be realized experimentally based on the advanced theory and technique in Bose-Einstein condensate (BEC) of molecule, micro-fabricated wave guide and simple quantum logic gate. Similarly, we can make an arbitrary n-particle entangled Greenberger Horne-Zeilinger (GHZ) state (n ≥ 4) teleported through this kind of quantum channel. It may have important applications due to its resource-economic and practical features.
文摘The GHZ states and W states are two fundamental types of three qubits quantum entangled states. For finding the knotted pictures of three nodes W states, on the one side, we empty any one node, thus obtaining three degenerated twonode W states, then we find the nonzero submatrix of the corresponding covariance correlation tensor in quantum network theory. On the other side, excepting the linkage 41 corresponding to Bell bases, we conjecture that the another one possible oriented link (which is composed of two-component knots entangled with each other and has four crossings) would be the required knotted pictures of the two nodes W states, thence obtain the nonzero submatrix of the Alexander relation matrix in the theory of knot crystals for these knotted pictures. The equality of the two nonzero submatfices of different kinds thus verify the exactness of our conjecture. The superposition of three knotted pictures of two-node W states from different choices of the emptied node gives the knotted pictures of three-node W states, thus shows the correspondence between three-node W states in quantum network theory and the oriented links in knot theory. Finally we point out that there is an intimate and simple relationship between the knotted pictures of GHZ states and W states.
文摘A scheme is proposed for generating entangled W states with four cavity modes. In this scheme, we send a V-type three-level atom through two identical two-mode cavities in succession. After the atom exits from the second cavity, the four cavity modes are prepared in the W state. On the other hand we can obtain three-atom W states by sending three V-type three-level atoms through a two-mode cavity in turn. The present scheme does not require conditional measurement, and it is easily generalized to preparing 2n-mode W states and n-atom W states.
基金Project supported by the National Basic Research Program of China (Grant No. 2010CB923202)the Specialized Research Fund for the Doctoral Program of Ministry of Education of China (Grant No.20090005120008)+1 种基金the Fundamental Research Funds for the Central Universities of Chinathe National Natural Science Foundation of China (Grant Nos. 60937003,61178010,and 61205117)
文摘We propose a practical entanglement concentration protocol (ECP) for a hybrid entangled state using quantum dots and a microcavity coupled system. A hybrid less-entangled state can he concentrated to a most-entangled state with a certain probability using only one ancillary single photon. Moreover, using this protocol, we can also concentrate an arbitrary three-particle less-entangled W state using two ancillary photons and classical communication. The proposed protocols provide us with a useful method to concentrate less-entangled states, which can he implemented with current technology.
基金supported by Natural Science Foundation of Jiangxi,China,(Grant Nos 0612006 and 2007GZW0819)the Scientific Research Foundation of Jiangxi Provincial Department of Education of China,(Grant No [2007]191)the Funds from East China Jiaotong University.
文摘Following the theoretical protocol described by Fortescue and Lo [Fortescue B and Lo H K 2007 Phys. Rev. Lett. 98 2605011, we present a scheme in which one can distill maximally entangled bi-partite states from a tri-partite W state with cavity QED. Our scheme enables the concrete physical system to realize its protocol. In our scheme, the rate distillation also asymptotically approaches one. Based on the present cavity QED techniques, we discuss the experimental feasibility.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 90503010,10874050,10975054,91021011 and 11005057)National Basic Research Program of China (Grant No. 2005CB724508)the Foundation from the Ministry of Education of China (Grant No. 200804870051)
文摘We propose two schemes for generating Greenberger-Horne-Zeilinger and W states of three distant atoms. In the present schemes, the atoms are individually trapped in three spatially separated optical cavities coupled by two optical fibres. Performing an adiabatic passage along dark states, the population of cavities and fibres excited is negligible under certain conditions. In addition, the spontaneous decay of atoms is also efficiently suppressed based on our proposals. Furthermore, the discussion about the entanglement fidelity is given and we point out that our schemes work robustly with small fluctuations of experimental parameters.
文摘The existence of decoherence-free subspace (DFS) has been discussed widely. In this paper, we propose an alternative scheme for generating the four-atom W states by manipulating DF qubits. The atoms are divided into two pairs and trapped in two separate optical cavities. Manipulation of atoms within DFS may generate a two-atom maximally entangled state in an individual cavity, which is a stable state. After driving the system out of DFS, the atoms will interact resonantly with the cavity field. The photons leaking from the cavities interfere at the beamsplitter, which destroys which-path information, and are finally detected by one of the detectors, leading to the generation of a W state. In addition, the numerical simulation indicates that the fidelity of the prepared state can, for a very wide parameter regime, be very close to unity.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10971247 and 10905016)Natural Science Foundation of Hebei Province of China (Grant Nos. F2009000311 and A2010000344)the Science Foundation of Hebei Normal University (Grant No. L2010Q04)
文摘In this paper, we investigate perfect quantum teleportation and dense coding by using an 2N-qubit W state channel. In the quantum teleportation scheme, an unknown N-qubit entangled state can be perfectly teleported. One ebit of entanglement and two bits of classical communication are consumed in the teleportation process, just like when using the Bell state channel. While N + 1 bits of classical information can be transmitted by only sending N particles in the dense coding protocol.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10504042)the Key Laboratory of Low Dimensional Quantum Structures and Quantum Control (Hunan Normal University)Ministry of Education of China (Grant No.QSQC0902)
文摘A simple scheme is proposed to generate the W state of N A-type neutral atoms trapped in an optical cavity via Raman transition. Conditional on no photon leakage from the cavity, the N-qubit W state can be prepared perfectly by turning on a classical coupling field for an appropriate time. Compared with the previous ones, our scheme requires neither individual laser addressing of the atoms, nor demand for controlling N atoms to go through an optical cavity simultaneously with a constant velocity. We investigate the influence of cavity decay using the quantum jump approach and show that the preparation time decreases and the success probability increases with atom number because of a collective enhancement of the coupling.
基金National Natural Science Foundation of China under Grant Nos.10575017 and 10547106
文摘Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only related to their coefficients and we successfully apply the general N-qubit W state to quantum state transferand quantum state prepare like that in two-qubit system.
基金Project supported by the National Natural Science Foundation of China(Grant No.61871234)sponsored by NUPTSF(Grant Nos.NY218097 and NY220178)。
文摘We propose a scheme to fast prepare the three-qubit W state via superadiabatic-based shortcuts in a circuit quantumelectrodynamics (circuit QED) system. We derive the effective Hamiltonian to suppress the unwanted transitions betweendifferent eigenstates by counterdiabatic driving, and obtain the W state with high-fidelity based on the superadiabaticpassage. The numerical simulation results demonstrate that the proposed scheme can accelerate the evolution, and is moreefficient than that with the adiabatic passage. In addition, the proposed scheme is robust to the decoherence caused by theresonator decay and qubit relaxation, and does not need additional parameters, which could be feasible in experiment.
基金supported by National Natural Science Foundation of China (NSFC) under Grant No.11271237 and No.61228305
文摘Quantum discord is the most prominent of quantum correlations, but it does not have unique generalizations to the multipartite case. W states are especially useful for secure communication. In this paper, we propose that the quantum correlation in generic three-qubit pure W states can be given by the two-qubit discords of these states.
文摘In this paper, two schemes for teleporting an unknown four-particle entangled W state is proposed. In the first scheme, two partial entangled four-particle states are used as quantum channels, while in the second scheme,four non-maximally entangled particle pairs are considered as quantum channels. It is shown that the teleportation can be successfully realized with certain probability, for both schemes, if a receiver adopts some appropriate unitary transformations. It is also shown that the successful probabilities of these two schemes are different.
基金Supported by the National Natural Science Foundation of China under Grant No.10704011the Research Programs of the Educational Office of Liaoning Province under Grant No.2008006
文摘A theoretical protocol of quantum dialogue is proposed,which uses a class of three-photon W states asquantum channel.After two-step security check,four-bit secret message can be transmitted to each other by transmittingof single photon with the aid of two-bit classical information.