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arXiv · 1304.7460

Towards loophole-free Bell inequality test with preselected unsymmetrical singlet states of light

M. Stobińska·F. Töppel·P. Sekatski·A. Buraczewski
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Abstract

Can a Bell test with no detection loophole be demonstrated for multi-photon entangled states of light within the current technology? We examine the possibility of a postselection-free CHSH-Bell inequality test wih an unsymmetrical polarization singlet. To that end we employ a preselection procedure which is performed prior to the test. It allows using imperfect (coarse-grained) binary photodetection in the test. We show an example of preselection scheme which improves violation of the CHSH inequality with the micro-macro polarization singlet produced by the optimal quantum cloning. The preselection is realized by a quantum filter which is believed to be not useful for this purpose.

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M. Stobińska, F. Töppel, P. Sekatski, A. Buraczewski. 2014-02-03. Towards loophole-free Bell inequality test with preselected unsymmetrical singlet states of light. https://doi.org/10.1103/physreva.89.022119

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