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Robustness of multiparty nonlocality to local decoherence

Sung Soon Jang·Yong Wook Cheong·Jaewan Kim·Hai-Woong Lee
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Abstract

We investigate the robustness of multiparty nonlocality under local decoherence, acting independently and equally on each subsystems. To be specific, we consider an N-qubit GHZ state under depolarization, dephasing, or dissipation channel, and tested the nonlocality by violation of Mermin-Klyshko inequality, which is one of Bell's inequalities for multi-qubit systems. The results show that the robustness of nonlocality increases with the number of qubits, and that the nonlocality of an N-qubit GHZ state with even N is extremely persistent against dephasing.

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Sung Soon Jang, Yong Wook Cheong, Jaewan Kim, Hai-Woong Lee. 2006-08-30. Robustness of multiparty nonlocality to local decoherence. https://doi.org/10.1103/physreva.74.062112

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