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arXiv · 1609.04811

Spin-parity effect in violation of bell's inequalities for entangled states of parallel polarization

Haifeng Zhang·Jianhua Wang·Zhigang Song·J. -Q. Liang·L. -F. Wei
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Abstract

Bell inequalities (BIs) derived in terms of quantum probability statistics are extended to general bipartite-entangled states of arbitrary spins with parallel polarization. The original formula of Bell for the two-spin singlet is slightly modified in the parallel configuration, while, the inequality for- mulated by Clauser-Horne-Shimony-Holt remains not changed. The violation of BIs indeed resulted from the quantum non-local correlation for spin-1=2 case. However, the inequalities are always satisfied for the spin-1 entangled states regardless of parallel or antiparallel polarizations of two spins. The spin parity effect originally demonstrated with the antiparallel spin-polarizations (Mod. Phys. Lett. B28, 145004) still exists for the parallel case. The quantum non-locality does not lead to the violation for integer spins due to the cancellation of non-local interference effects by the quantum statistical-average. Again the violation of BIs seems a result of the measurement induced nontrivial Berry-phase for half-integer spins.

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Haifeng Zhang, Jianhua Wang, Zhigang Song, J. -Q. Liang, L. -F. Wei. 2016-09-15. Spin-parity effect in violation of bell's inequalities for entangled states of parallel polarization. https://doi.org/10.1142/s0217984917500324

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