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arXiv · 1310.6300

Bell-type inequality and quantum nonlocality in four-qubit systems

Dong Ding·Fengli Yan·Ting Gao
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Abstract

We present a Bell-type inequality for four-qubit systems. Using the inequality we investigate quantum nonlocality of a generic family of states $\left|G_{abcd}\right >$ [Phys. Rev. A 65, 052112 (2002)] and several canonical four-qubit entangled states. It has been demonstrated that the inequality is maximally violated by so called "four-qubit maximal entangled state $\left|G_{m}\right >$" and it is also violated by the four-qubit W state and a special family of states $\left|G_{ab00}\right >$. Moreover, a useful entanglement-nonlocality relationship for the family of states $\left|G_{ab00}\right >$ is obtained.

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Dong Ding, Fengli Yan, Ting Gao. 2013-10-23. Bell-type inequality and quantum nonlocality in four-qubit systems. https://doi.org/10.1088/1674-1056/24/7/070301

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