摘要
Tis paper demonstrates that multipartite Bell-inequality violations can be fully destroyed in a finite time in three- qubit states coupled to a general XY spin-chain with a three-site interaction environment. The Mermin Ardehali- Belinksii-Klyshko inequality is used to detect the degree of nonlocality, as measured by the extent of their violations. The effects of system-environment couplings, the size of degrees of freedom of the environment and the strength of the three-site interaction on the Bell-inequality violations are given. The results indicate that the Bell-inequality violations of the tripartite states will be completely destroyed by decoherence under certain conditions for the GHZ state. The decoherence-free subspaces of our model are identified and the entanglement of quantum states is also discussed.
Tis paper demonstrates that multipartite Bell-inequality violations can be fully destroyed in a finite time in three- qubit states coupled to a general XY spin-chain with a three-site interaction environment. The Mermin Ardehali- Belinksii-Klyshko inequality is used to detect the degree of nonlocality, as measured by the extent of their violations. The effects of system-environment couplings, the size of degrees of freedom of the environment and the strength of the three-site interaction on the Bell-inequality violations are given. The results indicate that the Bell-inequality violations of the tripartite states will be completely destroyed by decoherence under certain conditions for the GHZ state. The decoherence-free subspaces of our model are identified and the entanglement of quantum states is also discussed.
基金
Project supported by the National Natural Science Foundation of China (Grant No.11004050)
the Scientific Research Fund of Hunan Provincial Education Department of China (Grant Nos.
09A013 and 10B013)
the Science and Technology Research Foundation of Hunan Province of China (Grant No.2010FJ4120)
the Excellent Talents Program of Hengyang Normal University of China (Grant No.2010YCJH01)
the Science Foundation of Hengyang Normal University of China (Grant Nos.10A46 and 10B69)
