Telecloning and its reverse process, referred to as remote quantum-information concentration (RQIC), have been attracting considerable interest because of their potential applications in quantum-information processing...Telecloning and its reverse process, referred to as remote quantum-information concentration (RQIC), have been attracting considerable interest because of their potential applications in quantum-information processing. The previous RQIC protocols were focused on the reverse process of the optimal universal telecloning. We here study the reverse process of ancilla-free phase-covariant telecloning (AFPCT). It is shown that the quantum information originally distributed into two spatially separated qubits from a single qubit via the optimal AFPCT procedure can be remotely concentrated back to a single qubit with a certain probability by using an asymmetric W state as the quantum channel.展开更多
We propose an experimentally feasible scheme to implement the optimal asymmetric economical 1→3 phasecovariant telecloning protocol, which works without ancilla, based on cavity quantum electrodynamics （QED）. The s...We propose an experimentally feasible scheme to implement the optimal asymmetric economical 1→3 phasecovariant telecloning protocol, which works without ancilla, based on cavity quantum electrodynamics （QED）. The scheme is insensitive to the cavity field states and the cavity decay. In the telecloning process, the cavity is only virtually excited, it greatly prolongs the efficient decoherent time. Therefore, the scheme may be experimentally realized in the field of current cavity QED techniques.展开更多
This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant i...This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant interaction, which is important in view of decoherence. Furthermore, the scheme is feasible based on current technologies.展开更多
This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D＇Ar]ano G M and Macchiave...This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D＇Ar]ano G M and Macchiavello C 2003 Phys. Rev. A 67 042306]. The derived transformations cover the previous contributions [Delgado Y, Lamata Let al, 2007 Phys. Rev. Lett. 98 150502] in which M must be odd.展开更多
In this paper, we derive the explicit transformations of the optimal 1→3, 4, 5 phase-covariant cloning in three dimensions, and then generalize them to the cases of 1 → M = 3n, 3n ＋ 1, 3n ＋ 2 （n ≥ 1 integer） cl...In this paper, we derive the explicit transformations of the optimal 1→3, 4, 5 phase-covariant cloning in three dimensions, and then generalize them to the cases of 1 → M = 3n, 3n ＋ 1, 3n ＋ 2 （n ≥ 1 integer） cloning. The clone fidelities are coincident with the theoretical bounds found.展开更多
By means of cavity-assisted photon interference, a simple scheme is proposed to implement a symmetric economical phase-covariant quantum cloning machine of two remote qubits, with each in a separate cavity. With our p...By means of cavity-assisted photon interference, a simple scheme is proposed to implement a symmetric economical phase-covariant quantum cloning machine of two remote qubits, with each in a separate cavity. With our present scheme, a high-fidelity cloning machine is realized. Our scheme may be quite useful in terms of distributed quantum information processing.展开更多
文摘Telecloning and its reverse process, referred to as remote quantum-information concentration (RQIC), have been attracting considerable interest because of their potential applications in quantum-information processing. The previous RQIC protocols were focused on the reverse process of the optimal universal telecloning. We here study the reverse process of ancilla-free phase-covariant telecloning (AFPCT). It is shown that the quantum information originally distributed into two spatially separated qubits from a single qubit via the optimal AFPCT procedure can be remotely concentrated back to a single qubit with a certain probability by using an asymmetric W state as the quantum channel.
基金Project supported by the National Natural Science Foundation of China(Grant No.10674001)the Personal Development Foundation of Anhui Province,China(Grant No.2008Z018)
文摘We propose an experimentally feasible scheme to implement the optimal asymmetric economical 1→3 phasecovariant telecloning protocol, which works without ancilla, based on cavity quantum electrodynamics （QED）. The scheme is insensitive to the cavity field states and the cavity decay. In the telecloning process, the cavity is only virtually excited, it greatly prolongs the efficient decoherent time. Therefore, the scheme may be experimentally realized in the field of current cavity QED techniques.
基金Project supported by the National Natural Science Foundation of China(Grant Nos10574022 and 10575022)the Funds of the Natural Science of Fujian Province,China(Grant Nos Z0512006 and A0210014)
文摘This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant interaction, which is important in view of decoherence. Furthermore, the scheme is feasible based on current technologies.
基金supported by the Natural Science Foundation of Hunan Province under Grant No. 06JJ50118the Key Project of Chinese Ministry of Education under Grant No. 206103+1 种基金the National Natural Science Foundation of China under Grant No. 10775048the National Fundamental Research Program of China under Grant No. 2007CB925204
基金supported by the National Natural Science Foundation of China (Grant No 10674001)the Program of the Education Department of Anhui Province of China (Grant No KJ2007A002)
文摘This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D＇Ar]ano G M and Macchiavello C 2003 Phys. Rev. A 67 042306]. The derived transformations cover the previous contributions [Delgado Y, Lamata Let al, 2007 Phys. Rev. Lett. 98 150502] in which M must be odd.
基金supported by the National Natural Science Foundation of China(Grant Nos.11074002,61073048,and 11104057)the Natural Science Foundationof the Education Department of Anhui Province,China(Grant Nos.KJ2010ZD08 and KJ2012A245)the Postgraduate Program of Huainan NormalUniversity of China
文摘In this paper, we derive the explicit transformations of the optimal 1→3, 4, 5 phase-covariant cloning in three dimensions, and then generalize them to the cases of 1 → M = 3n, 3n ＋ 1, 3n ＋ 2 （n ≥ 1 integer） cloning. The clone fidelities are coincident with the theoretical bounds found.
文摘By means of cavity-assisted photon interference, a simple scheme is proposed to implement a symmetric economical phase-covariant quantum cloning machine of two remote qubits, with each in a separate cavity. With our present scheme, a high-fidelity cloning machine is realized. Our scheme may be quite useful in terms of distributed quantum information processing.
基金supported by National Natural Science Foundation of China under Grant No.10674001the Program of the Education Department of Anhui Province under Grant No.KJ2007A002the Youth Program of Fu Yang Normal College under Grant No.2008LQ04
基金The project supported by National Natural Science Foundation of China under Grant No. 10574022 and Natural Science Foundation of Fujian Province under Grant No. Z0512006
