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.
@article{arxiv.quant-ph/0701191,
title = {Minimum detection efficiency for a loophole-free atom-photon Bell experiment},
author = {Adan Cabello and Jan-Åke Larsson},
journal= {arXiv preprint arXiv:quant-ph/0701191},
year = {2022}
}