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Nonlocality of cluster states of qubits

Valerio Scarani·Antonio Acin·Emmanuel Schenck·Markus Aspelmeyer
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Abstract

We investigate cluster states of qubits with respect to their non-local properties. We demonstrate that a Greenberger-Horne-Zeilinger (GHZ) argument holds for any cluster state: more precisely, it holds for any partial, thence mixed, state of a small number of connected qubits (five, in the case of one-dimensional lattices). In addition, we derive a new Bell inequality that is maximally violated by the 4-qubit cluster state and is not violated by the 4-qubit GHZ state.

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Valerio Scarani, Antonio Acin, Emmanuel Schenck, Markus Aspelmeyer. 2005-04-25. Nonlocality of cluster states of qubits. https://doi.org/10.1103/physreva.71.042325

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