We propose a simple experimental scheme in which an unknown two-qubit state is faithfully and deterministically teleported from Alice to Bob. The scheme is constructed with four photons from parametric down conversion...We propose a simple experimental scheme in which an unknown two-qubit state is faithfully and deterministically teleported from Alice to Bob. The scheme is constructed with four photons from parametric down conversion, linear optical elements, and conventional photon detectors, all of which are available in current technology. It is shown that the probability of successful teleportation ideally reaches 100% based on single-photon two-qubit-assisted Bell-state measurement, which can distinguish all four Bell-states simultaneously via conventional photon detectors. By generalizing the scheme, the teleportation of an unknown multi-qubit system can also be realized.展开更多
We propose two schemes to concentrate unknown nonmaximally tripartite GHZ entangled states via linear optical elements. The finial maximally entangled states obtained from our schemes are shared by two or three partie...We propose two schemes to concentrate unknown nonmaximally tripartite GHZ entangled states via linear optical elements. The finial maximally entangled states obtained from our schemes are shared by two or three parties. Our schemes only need polarizing beam splitters and single-photon detectors. In addition, the schemes can be demonstrated within current experimental technology.展开更多
Entanglement plays an important role in quantum information science, especially in quantum communications. Here we present an efficient entanglement concentration protocol(ECP) for nonlocal atom systems in the partial...Entanglement plays an important role in quantum information science, especially in quantum communications. Here we present an efficient entanglement concentration protocol(ECP) for nonlocal atom systems in the partially entangled W-class states, using the single-photon input-output process regarding low-Q cavity and linear optical elements. Compared with previously published ECPs for the concentration of non-maximally entangled atomic states, our protocol is much simpler and more efficient as it employs the Faraday rotation in cavity quantum electrodynamics(QED) and the parameter-splitting method. The Faraday rotation requires the cavity with low-Q factor and weak coupling to the atom, which makes the requirement for entanglement concentration much less stringent than the previous methods, and achievable with current cavity QED techniques. The parameter-splitting method resorts to linear-optical elements only. This ECP has high efficiency and fidelity in realistic experiments, and some imperfections during the experiment can be avoided efficiently with currently available techniques.展开更多
In this paper, we present a linear optical scheme for optimal unambiguous discrimination among nonorthogonal quantum states in terms of the multiple-rail and polarization representation of a single photon. In our sche...In this paper, we present a linear optical scheme for optimal unambiguous discrimination among nonorthogonal quantum states in terms of the multiple-rail and polarization representation of a single photon. In our scheme, discriminated quantum states are expressed by using the spatial degree of freedom of a single photon while the polarization degree of freedom of the single photon is used to act as an auxiliary qubit. The optical components used in our scheme are only passive linear optical elements such as polarizing beam splitters, wave plates, polarizers, single photon detectors, and single photon source.展开更多
This paper proposes a scheme for entanglement concentration of unknown triparticle W class states with a certain probability. This protocol is mainly based on the coincidences of single-photon detectors and requires s...This paper proposes a scheme for entanglement concentration of unknown triparticle W class states with a certain probability. This protocol is mainly based on the coincidences of single-photon detectors and requires single-photon detectors and linear optical elements. The scheme is feasible within current technology.展开更多
Measurement-based quantum computation in an optical setup shows great promise towards the implementation oflarge-scale quantum computation. The difficulty of measurement-based quantum computation lies in the preparati...Measurement-based quantum computation in an optical setup shows great promise towards the implementation oflarge-scale quantum computation. The difficulty of measurement-based quantum computation lies in the preparation ofcluster state. In this paper, we propose the method of generating the large-scale cluster state, which is a platform formeasurement-based quantum computation. In order to achieve more complex quantum circuits, the preparation protocolof N-photon cluster state will be proposed as a generalization of the preparation of four- and five-photon cluster states.Furthermore, our proposal is experimentally feasible.展开更多
We propose feasible experimental schemes for preparing all five-photon graph states. Our schemes require only linear optical elements, photon detectors and post-selection, which are available in current experiment so ...We propose feasible experimental schemes for preparing all five-photon graph states. Our schemes require only linear optical elements, photon detectors and post-selection, which are available in current experiment so that these schemes are within the reach of the current technology.展开更多
Inspired by a recent paper [2002 J. Opt. B 4 316] we present an alternative scheme to teleport an entanglement of zero- and one-photon states of a running-wave field. The scheme employs only linear optical elements pl...Inspired by a recent paper [2002 J. Opt. B 4 316] we present an alternative scheme to teleport an entanglement of zero- and one-photon states of a running-wave field. The scheme employs only linear optical elements plus single-photon sources and detectors.展开更多
We propose a scheme to effectively generate a four-photon path-entangled number state [the NOON state i.e. 1/√2（｜N,0〉 ＋ ｜0, N〉）] for the demonstration of four-photon de Broglie wavelength. Our scheme rcquires...We propose a scheme to effectively generate a four-photon path-entangled number state [the NOON state i.e. 1/√2（｜N,0〉 ＋ ｜0, N〉）] for the demonstration of four-photon de Broglie wavelength. Our scheme rcquires only linear optical elements, photon detectors and post-selections which are all within the reach of current technology.展开更多
In this paper, we present a probabilistic teleportation scheme for unknown bipartite entangled state. By using linear optical elements, we convert the Bell-state measurement into separated single-qubit measurements.
This paper proposes a scheme to generate arbitrary four-atom entangled decoherence-free states by using simple linear optical elements, four one-sided cavities in which four atoms are confined respectively. By conveni...This paper proposes a scheme to generate arbitrary four-atom entangled decoherence-free states by using simple linear optical elements, four one-sided cavities in which four atoms are confined respectively. By conveniently tuning the titled angle of one half-wave plate, it can obtain arbitrary four-atom entangled decoherence-free states with a successful probability of 1 as long as there is no photon loss.展开更多
文摘We propose a simple experimental scheme in which an unknown two-qubit state is faithfully and deterministically teleported from Alice to Bob. The scheme is constructed with four photons from parametric down conversion, linear optical elements, and conventional photon detectors, all of which are available in current technology. It is shown that the probability of successful teleportation ideally reaches 100% based on single-photon two-qubit-assisted Bell-state measurement, which can distinguish all four Bell-states simultaneously via conventional photon detectors. By generalizing the scheme, the teleportation of an unknown multi-qubit system can also be realized.
基金The project supported by the Natural Science Foundation of the Education Department of Anhui Province under Grant Nos. 2006kj070A and 2006kj057B, and the Talent Foundation of Anhui University
文摘We propose two schemes to concentrate unknown nonmaximally tripartite GHZ entangled states via linear optical elements. The finial maximally entangled states obtained from our schemes are shared by two or three parties. Our schemes only need polarizing beam splitters and single-photon detectors. In addition, the schemes can be demonstrated within current experimental technology.
基金supported by the National Natural Science Foundation of China(Grant Nos.61471050,61377097,11404031 and 61571060)the Fok Ying-Tong Education Foundation for Young Teachers in the Higher Education Institutions of China(Grant No.151063)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.2015RC28)the Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications)(Grant No.IPOC2015ZT05)
文摘Entanglement plays an important role in quantum information science, especially in quantum communications. Here we present an efficient entanglement concentration protocol(ECP) for nonlocal atom systems in the partially entangled W-class states, using the single-photon input-output process regarding low-Q cavity and linear optical elements. Compared with previously published ECPs for the concentration of non-maximally entangled atomic states, our protocol is much simpler and more efficient as it employs the Faraday rotation in cavity quantum electrodynamics(QED) and the parameter-splitting method. The Faraday rotation requires the cavity with low-Q factor and weak coupling to the atom, which makes the requirement for entanglement concentration much less stringent than the previous methods, and achievable with current cavity QED techniques. The parameter-splitting method resorts to linear-optical elements only. This ECP has high efficiency and fidelity in realistic experiments, and some imperfections during the experiment can be avoided efficiently with currently available techniques.
基金Project supported by the National Fundamental Research Program （Grant No 2001CB309310）, the National Natural Science Foundation of China （Grant Nos 90203018 and 10325523）, the Scientific Research Fund of Hunan Provincial Education Department of China （Grant No 04C385）, the Natural Science Foundation of Hunan Province of China （Grant No 05JJ30012） and the Science Foundation of Hunan Normal University of China.
文摘In this paper, we present a linear optical scheme for optimal unambiguous discrimination among nonorthogonal quantum states in terms of the multiple-rail and polarization representation of a single photon. In our scheme, discriminated quantum states are expressed by using the spatial degree of freedom of a single photon while the polarization degree of freedom of the single photon is used to act as an auxiliary qubit. The optical components used in our scheme are only passive linear optical elements such as polarizing beam splitters, wave plates, polarizers, single photon detectors, and single photon source.
基金Project supported by the Natural Science Foundation of the Education Department of Anhui Province, China （Grant No 2006kj070A） and Anhui Provincial Natural Science Foundation, China （Grant No 03042401） and the Talent Foundation of Anhui University, China.
文摘This paper proposes a scheme for entanglement concentration of unknown triparticle W class states with a certain probability. This protocol is mainly based on the coincidences of single-photon detectors and requires single-photon detectors and linear optical elements. The scheme is feasible within current technology.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12025401 and U1930402).
文摘Measurement-based quantum computation in an optical setup shows great promise towards the implementation oflarge-scale quantum computation. The difficulty of measurement-based quantum computation lies in the preparation ofcluster state. In this paper, we propose the method of generating the large-scale cluster state, which is a platform formeasurement-based quantum computation. In order to achieve more complex quantum circuits, the preparation protocolof N-photon cluster state will be proposed as a generalization of the preparation of four- and five-photon cluster states.Furthermore, our proposal is experimentally feasible.
文摘We propose feasible experimental schemes for preparing all five-photon graph states. Our schemes require only linear optical elements, photon detectors and post-selection, which are available in current experiment so that these schemes are within the reach of the current technology.
文摘Inspired by a recent paper [2002 J. Opt. B 4 316] we present an alternative scheme to teleport an entanglement of zero- and one-photon states of a running-wave field. The scheme employs only linear optical elements plus single-photon sources and detectors.
基金Project supported by the National Natural Science Foundation of China (Grant No )the CAS and the National Fundamental Research Program (Grant No 2006CB921900)
文摘We propose a scheme to effectively generate a four-photon path-entangled number state [the NOON state i.e. 1/√2（｜N,0〉 ＋ ｜0, N〉）] for the demonstration of four-photon de Broglie wavelength. Our scheme rcquires only linear optical elements, photon detectors and post-selections which are all within the reach of current technology.
基金The project supported by the Natural Science Foundation of the Education Department of Anhui Province under Grant Nos. 2006kj070A and 2006kj057B, National Natural Science Foundation of China under Grant No. 10574001, and the Talent Foundation of Anhui University
文摘In this paper, we present a probabilistic teleportation scheme for unknown bipartite entangled state. By using linear optical elements, we convert the Bell-state measurement into separated single-qubit measurements.
基金Project supported by the National Natural Science Foundation of China (Grant No 60667001)the Science Foundation of Yanbian University,China (Grant No 2007-35)
文摘This paper proposes a scheme to generate arbitrary four-atom entangled decoherence-free states by using simple linear optical elements, four one-sided cavities in which four atoms are confined respectively. By conveniently tuning the titled angle of one half-wave plate, it can obtain arbitrary four-atom entangled decoherence-free states with a successful probability of 1 as long as there is no photon loss.
