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arXiv · 2501.03373

W-class states-identification and quantification of Bell-CHSH inequalities' violation

Joanna K. Kalaga·Wiesław Leoński·Jan Peřina Jr
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Abstract

We discuss a family of W-class states describing three-qubit systems. For such systems, we analyze the relations between the entanglement measures and the nonlocality parameter for a two-mode mixed state related to the two-qubit subsystem. We find the conditions determining the boundary values of the negativity, parameterized by concurrence, for violating the Bell-CHSH inequality. Additionally, we derive the value ranges of the mixedness measure, parameterized by concurrence and negativity for the qubit--qubit mixed state, guaranteeing the violation and non-violation of the Bell-CHSH inequality.

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Joanna K. Kalaga, Wiesław Leoński, Jan Peřina Jr. 2025-01-06. W-class states-identification and quantification of Bell-CHSH inequalities' violation. https://doi.org/10.3390/e26121107

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