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Violation of Bell's Inequality with Photons from Independent Sources

T. B. Pittman·J. D. Franson
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Abstract

We report a violation of Bell's inequality using one photon from a parametric down-conversion source and a second photon from an attenuated laser beam. The two photons were entangled at a beam splitter using the post-selection technique of Shih and Alley [Phys. Rev. Lett. 61, 2921 (1988)]. A quantum interference pattern with a visibility of 91% was obtained using the photons from these independent sources, as compared with a visibility of 99.4% using two photons from a central parametric down-conversion source.

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T. B. Pittman, J. D. Franson. 2003-05-12. Violation of Bell's Inequality with Photons from Independent Sources. https://doi.org/10.1103/physrevlett.90.240401

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