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Quadratic Bell inequalities as tests for multipartite entanglement

Jos Uffink
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Abstract

This letter presents quantum mechanical inequalities which distinguish, for systems of $N$ spin-$\half$ particles ($N>2$), between fully entangled states and states in which at most $N-1$ particles are entangled. These inequalities are stronger than those obtained by Gisin and Bechmann-Pasquinucci [Phys.\ Lett. A {\bf 246}, 1 (1998)] and by Seevinck and Svetlichny [quant-ph/0201046].

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Jos Uffink. 2002-05-06. Quadratic Bell inequalities as tests for multipartite entanglement. https://doi.org/10.1103/physrevlett.88.230406

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