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Minimum detection efficiency for a loophole-free atom-photon Bell experiment

Adan Cabello·Jan-Åke Larsson
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Abstract

In Bell experiments, one problem is to achieve high enough photodetection to ensure that there is no possibility of describing the results via a local hidden-variable model. Using the Clauser-Horne inequality and a two-photon non-maximally entangled state, a photodetection efficiency higher than 0.67 is necessary. Here we discuss atom-photon Bell experiments. We show that, assuming perfect detection efficiency of the atom, it is possible to perform a loophole-free atom-photon Bell experiment whenever the photodetection efficiency exceeds 0.50.

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Adan Cabello, Jan-Åke Larsson. 2007-01-26. Minimum detection efficiency for a loophole-free atom-photon Bell experiment. https://doi.org/10.1103/physrevlett.98.220402

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