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arXiv · 1308.0131

Violation of Bell inequality in perfect translation invariant systems

Zhao-Yu Sun·Yu-Ying Wu·Hai-Lin Huang·Bo-Jun Chen·Bo Wang
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Abstract

Bell inequalities and nonlocality have been widely studied in one-dimensional quantum systems. As a kind of quantum correlation, it is expected that bipartite nonlocaity should be present in quantum systems, just as bipartite entanglement does. Surprisingly, for various models, two-qubit states do not violate Bell inequalities, i.e., they are local. Recently, it is realized that the results are related to the monogamy trade-off obeyed by bipartite Bell correlations, thus it is believed that for general translation invariant systems, two-qubit states should not violate the Bell inequality(Oliveira, EPL 100, 60004 (2012)). In this report, we will demonstrate that in perfect translation invariant systems, the Bell inequality can be violated. A nontrivial model is constructed to confirm the conclusion.

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Zhao-Yu Sun, Yu-Ying Wu, Hai-Lin Huang, Bo-Jun Chen, Bo Wang. 2013-08-01. Violation of Bell inequality in perfect translation invariant systems. https://doi.org/10.1103/physreva.88.054101

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