Maximum violation of Wigner inequality for two-spin entangled states with parallel and antiparallel polarizations

Yan Gu, Haifeng Zhang, Zhigang Song, J.-Q. Liang, L.-F. Wei
2018 International Journal of Quantum Information  
The experimental test of Bell's inequality is mainly focused on Clauser-Horne-Shimony-Holt (CHSH) form, which provides a quantitative bound, while little attention has been pained on the violation of Wigner inequality (WI). Based on the spin coherent state quantum probability statistics we in the present paper extend the WI and its violation to arbitrary two-spin entangled states with antiparallel and parallel spin-polarizations. The local part of density operator gives rise to the WI while the
more » ... violation is a direct result of non-local interference between two components of the entangled states. The Wigner measuring outcome correlation denoted by W is always less than or at most equal to zero for the local realist model ( regardless of the specific initial state. On the other hand the violation ofWI is characterized by any positive value of W, which possesses a maximum violation bound W_ =1/2. We conclude that the WI is equally convenient for the experimental test of violation by the quantum entanglement.
doi:10.1142/s0219749918500417 fatcat:nkuyvrkwjfgqvhirgcjtozihse