Bell's Inequality and Entanglement in Qubits

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.

10 pages

References in corpus (4)

• Bipartite entanglement and entropic boundary law in lattice spin systems
• Entanglement Entropy as a Portal to the Physics of Quantum Spin Liquids
• Experimental Identification of Non-Abelian Topological Orders on a Quantum Simulator
• Revisiting Entanglement Entropy of Lattice Gauge Theories