In this paper, we propose a protocol to deterministically teleport an unknown mixed state of qubit by utilizing a maximally bipartite entangled state of qubits as quantum channel. Ira non-maximally entangled bipartite...In this paper, we propose a protocol to deterministically teleport an unknown mixed state of qubit by utilizing a maximally bipartite entangled state of qubits as quantum channel. Ira non-maximally entangled bipartite pure state is employed as quantum channel, the unknown mixed quantum state of qubit can be teleported with 1 -√ 1- C^2 probability, where C is the concurrence of the quantum channel. The protocol can also be generalized to teleport a mixed state of qudit or a multipartite mixed state. More important purpose is that, on the basis of the protocol, the teleportation of an arbitrary multipartite （pure or mixed） quantum state can be decomposed into the teleportation of each subsystem by employing separate entangled states as quantum channels. In the case of deterministic teleportation, Bob only needs to perform unitary transformations on his single particles in order to recover the initial teleported multipartite quantum state.展开更多
A scheme is proposed for the controlled teleportation of an arbitrary two-atom state via special W-type entangled states and QED cavity. The scheme does not involve the direct joint Bell-state-measurement （BSM）. We ...A scheme is proposed for the controlled teleportation of an arbitrary two-atom state via special W-type entangled states and QED cavity. The scheme does not involve the direct joint Bell-state-measurement （BSM）. We show that the quantum information is split into two parts~ thus the original atomic state cannot be perfectly restored by the receiver without the other agent＇s collaboration and classical communication. In addition, the physical realization of this scheme is not difficult.展开更多
A theoretical quantum communication scheme based on entanglement swapping and superdense coding is proposed with a 3-dimensional Bell state and 2-dimensional Bell state function as quantum channel,quantum key distribu...A theoretical quantum communication scheme based on entanglement swapping and superdense coding is proposed with a 3-dimensional Bell state and 2-dimensional Bell state function as quantum channel,quantum key distribution and quantum secure direct communication can be simultaneously accomplished in the scheme.The scheme is secure and has high source capacity.At last,we generalize the quantum communication scheme to d-dimensional quantum channel.展开更多
We study a special two-atom entanglement case in assumed cavity QED experiment in which only one atom effectively exchanges a single photon with a cavity mode. We compute two-atom entanglement under position-dependent...We study a special two-atom entanglement case in assumed cavity QED experiment in which only one atom effectively exchanges a single photon with a cavity mode. We compute two-atom entanglement under position-dependent atomic resonant dipole-dipole interaction （RDDI） for large interatomic separation limit. We show that the RDDI, even t, hat which is much smaller than the maximal atomic Rabi frequency, can induce distinct diatom entanglement. The peak entanglement reaches a maximum when RDDI strength can compare with the Rabi frequency of an atom.展开更多
We propose a more efficient and reliable scheme for transferring quantum states between distant atoms than previous schemes based on resonant atom-cavity interaction.In addition,our system can also be used to implemen...We propose a more efficient and reliable scheme for transferring quantum states between distant atoms than previous schemes based on resonant atom-cavity interaction.In addition,our system can also be used to implement a controlled phase gate with high fidelity.展开更多
We construct a novelΛ-type system via the dressed states formed by the coupling between a superconducting qubit and a transmission line resonator(TLR).Compared with the conventional three-level structure,our model av...We construct a novelΛ-type system via the dressed states formed by the coupling between a superconducting qubit and a transmission line resonator(TLR).Compared with the conventional three-level structure,our model averts the decay of excited states.We choose the two lowest energy dressed states as the logical states.The single qubit quantum gate can be realized by the adiabatic passage and three-step operation method,respectively.Based on realistic parameters,the feasibility of the adiabatic passage method is discussed.Also,we calculate the fidelity(0.9996)of realizing the single qubit gate with the three-step operation method.展开更多
Generalized Yang-Mills theory has a covariant derivative, which contains both vector and scalar gauge bosons. Based on this theory, we construct a strong interaction model by using the group U（4）. By using this U（4...Generalized Yang-Mills theory has a covariant derivative, which contains both vector and scalar gauge bosons. Based on this theory, we construct a strong interaction model by using the group U（4）. By using this U（4） generalized Yang-Mills model, we also obtain a gauge potential solution, which can be used to explain the asymptotic behavior and color confinement.展开更多
A maximally generalized Yang-Mills model, which contains, besides the vector part Vμ, also an axial-vector part Aμ, a scalar part S, a pseudoscalar part P, and a tensor part Tμv, is constructed and the dynamical br...A maximally generalized Yang-Mills model, which contains, besides the vector part Vμ, also an axial-vector part Aμ, a scalar part S, a pseudoscalar part P, and a tensor part Tμv, is constructed and the dynamical breaking of gauge symmetry in the model is also discussed. It is shown, in terms of the Nambu Jona-Lasinio mechanism, that the gauge symmetry breaking can be realized dynamically in the maximally generalized Yang-Mills model. The combination of the maximally generalized Yang-Mills model and the NJL mechanism provides a way to overcome the difficulties related to the Higgs field and the Higgs mechanism in the usual spontaneous symmetry breaking theory.展开更多
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10575017 and 60472017
文摘In this paper, we propose a protocol to deterministically teleport an unknown mixed state of qubit by utilizing a maximally bipartite entangled state of qubits as quantum channel. Ira non-maximally entangled bipartite pure state is employed as quantum channel, the unknown mixed quantum state of qubit can be teleported with 1 -√ 1- C^2 probability, where C is the concurrence of the quantum channel. The protocol can also be generalized to teleport a mixed state of qudit or a multipartite mixed state. More important purpose is that, on the basis of the protocol, the teleportation of an arbitrary multipartite （pure or mixed） quantum state can be decomposed into the teleportation of each subsystem by employing separate entangled states as quantum channels. In the case of deterministic teleportation, Bob only needs to perform unitary transformations on his single particles in order to recover the initial teleported multipartite quantum state.
基金The project supported by National Natural Science Foundation of China under Grant Nos.60472017,10575017,and 10704011Science Foundation of the Educational Department of Laioning Province under Grant No.2006B014
文摘A scheme is proposed for the controlled teleportation of an arbitrary two-atom state via special W-type entangled states and QED cavity. The scheme does not involve the direct joint Bell-state-measurement （BSM）. We show that the quantum information is split into two parts~ thus the original atomic state cannot be perfectly restored by the receiver without the other agent＇s collaboration and classical communication. In addition, the physical realization of this scheme is not difficult.
基金supported by National Natural Science Foundation of China under Grant No.60703100
文摘A theoretical quantum communication scheme based on entanglement swapping and superdense coding is proposed with a 3-dimensional Bell state and 2-dimensional Bell state function as quantum channel,quantum key distribution and quantum secure direct communication can be simultaneously accomplished in the scheme.The scheme is secure and has high source capacity.At last,we generalize the quantum communication scheme to d-dimensional quantum channel.
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10347103, 10305002, and 60472017
文摘We study a special two-atom entanglement case in assumed cavity QED experiment in which only one atom effectively exchanges a single photon with a cavity mode. We compute two-atom entanglement under position-dependent atomic resonant dipole-dipole interaction （RDDI） for large interatomic separation limit. We show that the RDDI, even t, hat which is much smaller than the maximal atomic Rabi frequency, can induce distinct diatom entanglement. The peak entanglement reaches a maximum when RDDI strength can compare with the Rabi frequency of an atom.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11175033 and 10875020.
文摘We propose a more efficient and reliable scheme for transferring quantum states between distant atoms than previous schemes based on resonant atom-cavity interaction.In addition,our system can also be used to implement a controlled phase gate with high fidelity.
基金Supported by the National Nature Science Foundation of China under Grants Nos 60703100,10775023 and 11175033the Fundamental Research Funds for the Central Universities under Grant No DUT10LK10.
文摘We construct a novelΛ-type system via the dressed states formed by the coupling between a superconducting qubit and a transmission line resonator(TLR).Compared with the conventional three-level structure,our model averts the decay of excited states.We choose the two lowest energy dressed states as the logical states.The single qubit quantum gate can be realized by the adiabatic passage and three-step operation method,respectively.Based on realistic parameters,the feasibility of the adiabatic passage method is discussed.Also,we calculate the fidelity(0.9996)of realizing the single qubit gate with the three-step operation method.
基金The project supported by the National Natural Science Foundation of China under Grant No. 10647106
文摘Generalized Yang-Mills theory has a covariant derivative, which contains both vector and scalar gauge bosons. Based on this theory, we construct a strong interaction model by using the group U（4）. By using this U（4） generalized Yang-Mills model, we also obtain a gauge potential solution, which can be used to explain the asymptotic behavior and color confinement.
基金The project supported by Nationai Naturai Science Foundation of China under Grant No. 10275008
文摘A maximally generalized Yang-Mills model, which contains, besides the vector part Vμ, also an axial-vector part Aμ, a scalar part S, a pseudoscalar part P, and a tensor part Tμv, is constructed and the dynamical breaking of gauge symmetry in the model is also discussed. It is shown, in terms of the Nambu Jona-Lasinio mechanism, that the gauge symmetry breaking can be realized dynamically in the maximally generalized Yang-Mills model. The combination of the maximally generalized Yang-Mills model and the NJL mechanism provides a way to overcome the difficulties related to the Higgs field and the Higgs mechanism in the usual spontaneous symmetry breaking theory.
