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arXiv · 1512.08848

Trade-off Relations of Bell Violations among Pairwise Qubit Systems

Hui-Hui Qin·Shao-Ming Fei·Xianqing Li-Jost
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Abstract

We investigate the nonlocality distributions among multiqubit systems based on the maximal violations of the Clauser-Horne-Shimony-Holt (CHSH) inequality of reduced pairwise qubit systems. We present a trade-off relation satisfied by these maximal violations, which gives rise to restrictions on the distribution of nonlocality among the subqubit systems. For a three-qubit system, it is impossible that all pairs of qubits violate the CHSH inequality, and once a pair of qubits violates the CHSH inequality maximally, the other two pairs of qubits must both obey the CHSH inequality. Detailed examples are given to illustrate the trade-off relations, and the trade-off relations are generalized to arbitrary multiqubit systems.

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Hui-Hui Qin, Shao-Ming Fei, Xianqing Li-Jost. 2015-12-30. Trade-off Relations of Bell Violations among Pairwise Qubit Systems. https://doi.org/10.1103/physreva.92.062339

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