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arXiv · 0709.1982

Entanglement detection via condition of quantum correlation

Che-Ming Li·Li-Yi Hsu·Yueh-Nan Chen·Der-San Chuu·Tobias Brandes
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Abstract

We develop a novel necessary condition of quantum correlation. It is utilized to construct $d$-level bipartite Bell-type inequality which is strongly resistant to noise and requires only analyses of $O(d)$ measurement outcomes compared to the previous result $O(d^{2})$. Remarkably, a connection between the arbitrary high-dimensional bipartite Bell-type inequality and entanglement witnesses is found. Through the necessary condition of quantum correlation, we propose that the witness operators to detect truly multipartite entanglement for a generalized Greenberger-Horne-Zeilinger (GHZ) state with two local measurement settings and a four-qubit singlet state with three settings. Moreover, we also propose the first robust entanglement witness to detect four-level tripartite GHZ state with only two local measurement settings.

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Che-Ming Li, Li-Yi Hsu, Yueh-Nan Chen, Der-San Chuu, Tobias Brandes. 2007-09-13. Entanglement detection via condition of quantum correlation. https://doi.org/10.1103/physreva.76.032313

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