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Chained Bell inequality experiment with high-efficiency measurements



Ting Rei Tan, Stephen D. Erickson, Peter L. Bierhorst, Daniel Kienzler, Scott C. Glancy, Emanuel H. Knill, Dietrich G. Leibfried, David J. Wineland, Yong Wan


We report correlation measurements on two 9Be+ ions that violate a chained Bell inequality obeyed by any local-realistic theory. The correlations can be modeled as derived from a mixture of a local-realistic probabilistic distribution and a distribution that violates the inequality. A statistical framework is formulated to quantify the local-realistic fraction allowable in the observed distribution without the fair-sampling or independent-and-identical-distributions assumptions. We exclude models of our experiment whose local-realistic fraction is above 0.362 at the 95% confidence level. This bound is significantly lower than 0.586, the minimum fraction derived from a perfect Clauser-Horne-Shimony-Holt inequality experiment. Furthermore, our data provides a device-independent certification of the deterministically created Bell states.
Physical Review Letters


Bell inequality, Foundation of quantum mechanics, Trapped ions, Quantum information processing
Created March 28, 2017, Updated August 20, 2018