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Bell inequalities versus entanglement and mixedness for a class of two - qubit states

L. Derkacz·L. Jakobczyk
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Abstract

For a class of mixed two -qubit states we show that it is not possible to discriminate between states violating or non - violating Bell - CHSH inequalities, knowing only their entanglement and mixedness. For a large set of possible values of these quantities, we construct pairs of states with the same entanglement and mixedness such that one state is violating but the other is non - violating Bell - CHSH inequality.

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L. Derkacz, L. Jakobczyk. 2004-02-17. Bell inequalities versus entanglement and mixedness for a class of two - qubit states. https://doi.org/10.1016/j.physleta.2004.06.007

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