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Family of Zeilinger-Horne-Greenberger "W" states lead to stronger nonclassicality than family of Greenberger-Horne-Zeilinger "GHZ" states

Aditi Sen De·Ujjwal Sen·Marcin Wiesniak·Dagomir Kaszlikowski·Marek Zukowski
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Abstract

The N-qubit states of the W class, for N>10, lead to more robust (against noise admixture) violations of local realism, than the GHZ states. These violations are most pronounced for correlations for a pair of qubits, conditioned on specific measurement results for the remaining (N-2) qubits. The considerations provide us with a qualitative difference between the W state and GHZ state in the situation when they are separately sent via depolarizing channels. For sufficiently high amount of noise in the depolarizing channel, the GHZ states cannot produce a distillable state between two qubits, whereas the W states can still produce a distillable state in a similar situation.

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Aditi Sen De, Ujjwal Sen, Marcin Wiesniak, Dagomir Kaszlikowski, Marek Zukowski. 2004-03-23. Family of Zeilinger-Horne-Greenberger "W" states lead to stronger nonclassicality than family of Greenberger-Horne-Zeilinger "GHZ" states. https://doi.org/10.1103/physreva.68.062306

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