A quantum encryption protocol based on Gaussian-modulated continuous variable EPR correlations is proposed. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate opt...A quantum encryption protocol based on Gaussian-modulated continuous variable EPR correlations is proposed. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate optical parametric amplifier （NOPA）. For general beam splitter eavesdropping strategy, the mutual information I（α, ε） between Alice and Eve is caJculated by employing Shannon information theory. Finally the security analysis is presented.展开更多
In this paper, the solution of the time-dependent Fokker-Planck equation of non-degenerate optical parametric amplification is used to deduce the condition demonstrating the Einstein-Podolsky-Rosen （EPR） paradox. Th...In this paper, the solution of the time-dependent Fokker-Planck equation of non-degenerate optical parametric amplification is used to deduce the condition demonstrating the Einstein-Podolsky-Rosen （EPR） paradox. The analytics and numerical calculation show the influence of pump depletion on the error in the measurement of continuous variables. The optimum realization of EPR paradox can be achieved by adjusting the parameter of squeezing. This result is of practical importance when the realistic experimental conditions are taken into consideration .展开更多
Since entangled multiple optical fields were identified as the building blocks of quantum networks,the quadripartite entangled optical fields have been produced by using four degenerate optical parametric amplifiers o...Since entangled multiple optical fields were identified as the building blocks of quantum networks,the quadripartite entangled optical fields have been produced by using four degenerate optical parametric amplifiers or two nondegenerate optical parametric amplifiers(NOPAs).However,realizing an efficient and compact source for multiple quantum users has remained an outstanding challenge,hindering their practical applications.Here,we proposed a compact and feasible scheme to deterministically entangle four spatially separated optical fields,employing only a single NOPA.Accordingly,two-sided output NOPA-based optical fields were coupled on a beam splitter network to form the quadripartite entangled state,causing the deterministic generation of both the Greenberger–Horne–Zeilinger(GHZ)and the linear cluster states in this compact entanglement source.We also obtained the optimal experimental parameters based on the simulation results,thereby providing a direct reference for experimental implementation.Our findings propose that the resultant GHZ and linear cluster states can be potentially applied in quantum-enhanced information science,specifically in quantum secret sharing,controlled quantum teleportation networks,and quantum-entangled atomic ensemble networks.展开更多
基金The project supported by National Natural Science Foundation of China under Grant No. 60472018
文摘A quantum encryption protocol based on Gaussian-modulated continuous variable EPR correlations is proposed. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate optical parametric amplifier （NOPA）. For general beam splitter eavesdropping strategy, the mutual information I（α, ε） between Alice and Eve is caJculated by employing Shannon information theory. Finally the security analysis is presented.
文摘In this paper, the solution of the time-dependent Fokker-Planck equation of non-degenerate optical parametric amplification is used to deduce the condition demonstrating the Einstein-Podolsky-Rosen （EPR） paradox. The analytics and numerical calculation show the influence of pump depletion on the error in the measurement of continuous variables. The optimum realization of EPR paradox can be achieved by adjusting the parameter of squeezing. This result is of practical importance when the realistic experimental conditions are taken into consideration .
基金supported by the National Natural Science Foundation of China(62122044,61925503,12004276,11904218,12147215,62135008,and 11834010)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi,China(2020L0516,2019L0092,and 2020L0029)+2 种基金the Program for the Innovative Talents of Higher Education Institutions of Shanxithe Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxithe fund for Shanxi“1331 Project”Key Subjects Construction.
文摘Since entangled multiple optical fields were identified as the building blocks of quantum networks,the quadripartite entangled optical fields have been produced by using four degenerate optical parametric amplifiers or two nondegenerate optical parametric amplifiers(NOPAs).However,realizing an efficient and compact source for multiple quantum users has remained an outstanding challenge,hindering their practical applications.Here,we proposed a compact and feasible scheme to deterministically entangle four spatially separated optical fields,employing only a single NOPA.Accordingly,two-sided output NOPA-based optical fields were coupled on a beam splitter network to form the quadripartite entangled state,causing the deterministic generation of both the Greenberger–Horne–Zeilinger(GHZ)and the linear cluster states in this compact entanglement source.We also obtained the optimal experimental parameters based on the simulation results,thereby providing a direct reference for experimental implementation.Our findings propose that the resultant GHZ and linear cluster states can be potentially applied in quantum-enhanced information science,specifically in quantum secret sharing,controlled quantum teleportation networks,and quantum-entangled atomic ensemble networks.
