An Ising-type atom-atom interaction is obtained in a fibre-connected three-atom system. The interaction is effective when △ ≈γ0 〉〉 g. The preparations of remote two-atom and three-atom entanglements governed by t...An Ising-type atom-atom interaction is obtained in a fibre-connected three-atom system. The interaction is effective when △ ≈γ0 〉〉 g. The preparations of remote two-atom and three-atom entanglements governed by this interaction are discussed in a specific parameter region. The overall two-atom entanglement is very small because of the existence of the third atom. However, the three-atom entanglement can reach a maximum very close to 1.展开更多
We present a remote three-party quantum state sharing （QSTS） scheme with three-atom Greenberger- Horne-Zeilinger （GHZ） states assisted by cavity QED and flying qubits. It exploits some photons to act as the flying...We present a remote three-party quantum state sharing （QSTS） scheme with three-atom Greenberger- Horne-Zeilinger （GHZ） states assisted by cavity QED and flying qubits. It exploits some photons to act as the flying qubits for setting up the quantum channel securely with three-atom systems in a GHZ state, which maybe make this remote QSTS scheme more practical than some other schemes based on atom systems only or ion-trap systems as photons interact with their environments weakly. The coherence of the stationary atom qubits in cavities provides the convenience for the parties in QSTS to check eavesdropping, different from entangled photon systems. Moreover, the present scheme works in a collective-noise condition and it may be more practical than others in applications in future.展开更多
Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy consumption.Three-atom metal clusters have been proved an ideal model to explore highly...Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy consumption.Three-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active sites.Here a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to Ag) clusters was reported.Three key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic performance.The d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was unveiled.By examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these systems.This work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.展开更多
We perform a research of the influence of atomic electrons correlation to some characteristics of the (e,2e) process on helium. The Hilleraas type J-matrix approach was used for numerical calculations.
Localization of the three-level Λ-type atomic system interacting with two orthogonal standing-wave fields is proposed. Two equal and tunable peaks in the 2D plane are obtained by the detunings corresponding to the tw...Localization of the three-level Λ-type atomic system interacting with two orthogonal standing-wave fields is proposed. Two equal and tunable peaks in the 2D plane are obtained by the detunings corresponding to the two orthogonal standing-wave fields when the decreasing intensities of spontaneously generated coherence (SGC) arise in the three-level Λ-type atomic system, while one circular ring with shrinking radii in the 2D plane is obtained by the adjusted phases and wave vectors of the standing-wave fields when the increasing intensities of SGC occur in the three-level Λ-type atomic system. 2D atom localization with the single ring with shrinking radii realized by the multiple parametric manipulations demonstrated the flexibility for our scheme.展开更多
We demonstrate that four sets of W-class states can be used to realize the deterministic quantum information splitting of an arbitrary three-atom state in cavity QED.The scheme does not involve Bell-state measurement ...We demonstrate that four sets of W-class states can be used to realize the deterministic quantum information splitting of an arbitrary three-atom state in cavity QED.The scheme does not involve Bell-state measurement and is insensitive to both the cavity decay and the thermal field.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos 10647107 and 10575017)
文摘An Ising-type atom-atom interaction is obtained in a fibre-connected three-atom system. The interaction is effective when △ ≈γ0 〉〉 g. The preparations of remote two-atom and three-atom entanglements governed by this interaction are discussed in a specific parameter region. The overall two-atom entanglement is very small because of the existence of the third atom. However, the three-atom entanglement can reach a maximum very close to 1.
基金Supported by the National Natural Science Foundation of China under Grant No.10974020the Fundamental Research Funds for the Central Universities
文摘We present a remote three-party quantum state sharing （QSTS） scheme with three-atom Greenberger- Horne-Zeilinger （GHZ） states assisted by cavity QED and flying qubits. It exploits some photons to act as the flying qubits for setting up the quantum channel securely with three-atom systems in a GHZ state, which maybe make this remote QSTS scheme more practical than some other schemes based on atom systems only or ion-trap systems as photons interact with their environments weakly. The coherence of the stationary atom qubits in cavities provides the convenience for the parties in QSTS to check eavesdropping, different from entangled photon systems. Moreover, the present scheme works in a collective-noise condition and it may be more practical than others in applications in future.
基金financially supported by CAS Project for Young Scientists in Basic Research (No.YSBR-050)the National Natural Science Foundation of China (Nos.92261113 and 222721809)Beijing Natural Science Foundation (No.2232035)。
文摘Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy consumption.Three-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active sites.Here a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to Ag) clusters was reported.Three key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic performance.The d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was unveiled.By examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these systems.This work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.
文摘We perform a research of the influence of atomic electrons correlation to some characteristics of the (e,2e) process on helium. The Hilleraas type J-matrix approach was used for numerical calculations.
文摘Localization of the three-level Λ-type atomic system interacting with two orthogonal standing-wave fields is proposed. Two equal and tunable peaks in the 2D plane are obtained by the detunings corresponding to the two orthogonal standing-wave fields when the decreasing intensities of spontaneously generated coherence (SGC) arise in the three-level Λ-type atomic system, while one circular ring with shrinking radii in the 2D plane is obtained by the adjusted phases and wave vectors of the standing-wave fields when the increasing intensities of SGC occur in the three-level Λ-type atomic system. 2D atom localization with the single ring with shrinking radii realized by the multiple parametric manipulations demonstrated the flexibility for our scheme.
基金Supported by the National Natural Science Foundation of China under Grant No. 60807014the Natural Science Foundation of Jiangxi Province under Grant No. 2009GZW0005+1 种基金the Research Foundation of State Key Laboratory of Advanced Optical Communication Systemsand Networks,Shanghai Jiao Tong Universitythe Research Foundation of the Education Department of Jiangxi Province under GrantNo. GJJ09153
文摘We demonstrate that four sets of W-class states can be used to realize the deterministic quantum information splitting of an arbitrary three-atom state in cavity QED.The scheme does not involve Bell-state measurement and is insensitive to both the cavity decay and the thermal field.
