We propose a protocol to generate a four-photon polarization-entangled cluster state with cross-Kerr nonlinearity by using the interference of polarized photons. The protocol is based on optical elements, cross-Kerr n...We propose a protocol to generate a four-photon polarization-entangled cluster state with cross-Kerr nonlinearity by using the interference of polarized photons. The protocol is based on optical elements, cross-Kerr nonlinearity, and homodyne measurement, therefore it is feasible with current experimental technology, The success probability of our protocol is optimal, this property makes our protocol more efficient than others in the applications of quantum communication.展开更多
A scheme is proposed for generating a multiphoton entangled cluster state among four modes. The scheme only uses Kerr medium, beam splitter and homodyne measurements on coherent light fields, which can be efficiently ...A scheme is proposed for generating a multiphoton entangled cluster state among four modes. The scheme only uses Kerr medium, beam splitter and homodyne measurements on coherent light fields, which can be efficiently made in quantum optical laboratories. The photon in the signal mode is prepared in a superposition state of the vacuum state and one-photon state while the probe beam is initially set in a coherent state superposition. The strong probe mode interacts successively with multiple signal-mode photons, each causing a conditional phase rotation in the probe mode. Subsequent momentum quadrature homodyne measurement of the probe mode will project the photons in the signal mode into the desired entangled states. It is shown that under certain conditions, the four-photon cluster state can be generated with high fidelity and high success probability, and the scheme is feasible by current experimental technology.展开更多
We propose a scheme for generating a hyperentangled four-photon cluster state that is simultaneously entangled in polarization modes and spatial modes. This scheme is based on linear optical elements, weak cross-Kerr ...We propose a scheme for generating a hyperentangled four-photon cluster state that is simultaneously entangled in polarization modes and spatial modes. This scheme is based on linear optical elements, weak cross-Kerr nonlinearity, and homodyne detection. Therefore, it is feasible with current experimental technology.展开更多
We propose two schemes for preparing four-photon cluster state through cross-Kerr nonlinearity. Two coherent fields interact when they enter a nonlinear Kerr medium. If the interaction time is chosen appropriately in ...We propose two schemes for preparing four-photon cluster state through cross-Kerr nonlinearity. Two coherent fields interact when they enter a nonlinear Kerr medium. If the interaction time is chosen appropriately in each Kerr medium, four-photon cluster state can be generated based on the results of two homodyne detectors in the first scheme. These schemes only use Kerr medium and homodyne measurements on coherent light fields, which can be effciently made in quantum optical laboratories. In addition, weak cross-Kerr nonlinearity is sufficient. All of the properties make these schemes feasible in experiments.展开更多
We propose an entanglement concentration protocol to concentrate an arbitrary partially-entangled four-photon cluster state.As a pioneering three-step entanglement concentration scheme,our protocol only needs a single...We propose an entanglement concentration protocol to concentrate an arbitrary partially-entangled four-photon cluster state.As a pioneering three-step entanglement concentration scheme,our protocol only needs a single-photon resource to assist the concentration in each step,which makes this protocol more economical.With the help of the linear optical elements and weak cross-Kerr nonlinearity,one can obtain a maximally-entangled cluster state via local operations and classical communication.Moreover,the protocol can be iterated to obtain a higher success probability and is feasible under current experimental conditions.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 61068001 and 11064016)
文摘We propose a protocol to generate a four-photon polarization-entangled cluster state with cross-Kerr nonlinearity by using the interference of polarized photons. The protocol is based on optical elements, cross-Kerr nonlinearity, and homodyne measurement, therefore it is feasible with current experimental technology, The success probability of our protocol is optimal, this property makes our protocol more efficient than others in the applications of quantum communication.
基金supported by the National Natural Science Foundation of China (Grant No. 11074002)the Doctoral Foundation of the Ministry of Education of China (Grant No. 20103401110003)the Personal Development Foundation of Anhui Province (Grant No. 2008Z018)
文摘A scheme is proposed for generating a multiphoton entangled cluster state among four modes. The scheme only uses Kerr medium, beam splitter and homodyne measurements on coherent light fields, which can be efficiently made in quantum optical laboratories. The photon in the signal mode is prepared in a superposition state of the vacuum state and one-photon state while the probe beam is initially set in a coherent state superposition. The strong probe mode interacts successively with multiple signal-mode photons, each causing a conditional phase rotation in the probe mode. Subsequent momentum quadrature homodyne measurement of the probe mode will project the photons in the signal mode into the desired entangled states. It is shown that under certain conditions, the four-photon cluster state can be generated with high fidelity and high success probability, and the scheme is feasible by current experimental technology.
基金supported by the Major Research Plan of the National Natural Science Foundation of China(Grant No.91121023)the National Natural Science Foundation of China(Grant Nos.60978009 and 61378012)+2 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20124407110009)the"973"Project(Grant Nos.2011CBA00200 and 2013CB921804)the PCSIRT(Grant No.IRT1243)
文摘We propose a scheme for generating a hyperentangled four-photon cluster state that is simultaneously entangled in polarization modes and spatial modes. This scheme is based on linear optical elements, weak cross-Kerr nonlinearity, and homodyne detection. Therefore, it is feasible with current experimental technology.
基金National Natural Science Foundation of China under Grant No.10574022the Natural Science Foundation of Fujian Province of China under Grant Nos.2007J0002 and 2007J0197the Foundation for Universities in Fujian Province under Grant No.2007F5041
文摘We propose two schemes for preparing four-photon cluster state through cross-Kerr nonlinearity. Two coherent fields interact when they enter a nonlinear Kerr medium. If the interaction time is chosen appropriately in each Kerr medium, four-photon cluster state can be generated based on the results of two homodyne detectors in the first scheme. These schemes only use Kerr medium and homodyne measurements on coherent light fields, which can be effciently made in quantum optical laboratories. In addition, weak cross-Kerr nonlinearity is sufficient. All of the properties make these schemes feasible in experiments.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61068001 and 11264042)the Talent Program of Yanbian University,China (Grant No. 950010001)+1 种基金the National Science Foundation for Post-doctoral Scientists of China (Grant No. 2012M520612)the Program for Chun Miao Excellent Talents of Department of Education of Jilin Province,China (Grant No. 201316)
文摘We propose an entanglement concentration protocol to concentrate an arbitrary partially-entangled four-photon cluster state.As a pioneering three-step entanglement concentration scheme,our protocol only needs a single-photon resource to assist the concentration in each step,which makes this protocol more economical.With the help of the linear optical elements and weak cross-Kerr nonlinearity,one can obtain a maximally-entangled cluster state via local operations and classical communication.Moreover,the protocol can be iterated to obtain a higher success probability and is feasible under current experimental conditions.
基金The Fund for Excellent Young Talents in the Higher Education Institutions of Anhui Province(No.2009SQRZ087)the Scientific Research Foundation for Young Teachers of Huaibei Normal University(No.2011xqxm38)
