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arXiv · 1705.06444

Bell's Inequality and Entanglement in Qubits

Po-Yao Chang·Su-Kuan Chu·Chen-Te Ma
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Abstract

We propose an alternative evaluation of quantum entanglement by measuring the maximum violation of the Bell's inequality without performing a partial trace operation. This proposal is demonstrated by bridging the maximum violation of the Bell's inequality and the concurrence of a pure state in an $n$-qubit system, in which one subsystem only contains one qubit and the state is a linear combination of two product states. We apply this relation to the ground states of four qubits in the Wen-Plaquette model and show that they are maximally entangled. A topological entanglement entropy of the Wen-Plaquette model could be obtained by relating the upper bound of the maximum violation of the Bell's inequality to the concurrences of a pure state with respect to different bipartitions.

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Po-Yao Chang, Su-Kuan Chu, Chen-Te Ma. 2017-05-18. Bell's Inequality and Entanglement in Qubits. https://doi.org/10.1007/jhep09(2017)100

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