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Two-setting Bell Inequalities for Graph States

Geza Toth·Otfried Guehne·Hans J. Briegel
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Abstract

We present Bell inequalities for graph states with high violation of local realism. In particular, we show that there is a two-setting Bell inequality for every nontrivial graph state which is violated by the state at least by a factor of two. These inequalities are facets of the convex polytope containing the many-body correlations consistent with local hidden variable models. We first present a method which assigns a Bell inequality for each graph vertex. Then for some families of graph states composite Bell inequalities can be constructed with a violation of local realism increasing exponentially with the number of qubits. We also suggest a systematic way for obtaining Bell inequalities with a high violation of local realism for arbitrary graphs.

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Geza Toth, Otfried Guehne, Hans J. Briegel. 2006-04-12. Two-setting Bell Inequalities for Graph States. https://doi.org/10.1103/physreva.73.022303

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