Physical Review Letters

Further evidence of nonclassical behavior in optical interference

Z. Y. Ou, L. Mandeļ

Published Jun 19, 1989• 73 citations

Abstract

It is demonstrated in a photon coincidence experiment with two photodetectors, in which signal and idler photons produced by parametric down-conversion are allowed to interfere, that the visibility of the interference pattern is well above 50% and remains unchanged when one of the two light beams is attenuated ninefold compared with the other. These results violate classical probability for light waves.

DOI: 10.1103/physrevlett.62.2941

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