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Analysis of coincidence-time loopholes in experimental Bell tests



B. G. Christensen, A. Hill, P. G. Kwiat, Emanuel Knill, Sae Woo Nam, Kevin Coakley, Scott Glancy, Krister Shalm, Y. Zhang


We apply a distance-based Bell-test analysis method ["Bell inequalities for continuously emitting sources" E. Knill et al. arXiv:14097732 (2014)] to three experimental data sets where conventional analyses failed or required additional assumptions. The first is produced from a classical source exploiting a "coincidence-time loophole" for which standard analysis falsely shows a Bell violation. The second data set is from a source previously shown to violate a Bell inequality; the distance-based analysis agrees with the previous results but with fewer assumptions. Lastly, the third data set does not show a violation with standard analysis despite the high source quality, but is shown to have a strong violation with the distance-based analysis method.
Physical Review A


Bell inequalities, coincidence detection, entanglement, photons


Christensen, B. , Hill, A. , Kwiat, P. , Knill, E. , Nam, S. , Coakley, K. , Glancy, S. , Shalm, K. and Zhang, Y. (2015), Analysis of coincidence-time loopholes in experimental Bell tests, Physical Review A, [online], (Accessed April 14, 2024)
Created March 3, 2015, Updated October 12, 2021