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Functional Bell inequalities can serve as a stronger entanglement witness

Aditi Sen De·Ujjwal Sen·Marek Zukowski
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Abstract

We consider a Bell inequality for a continuous range of settings of the apparatus at each site. This "functional" Bell inequality gives a better range of violation for generalized GHZ states. Also a family of N-qubit bound entangled states violate this inequality for N>5.

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Aditi Sen De, Ujjwal Sen, Marek Zukowski. 2002-06-24. Functional Bell inequalities can serve as a stronger entanglement witness. https://doi.org/10.1103/physreva.66.062318

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