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Identifying entanglement using quantum "ghost" interference and imaging

Milena D'Angelo·Yoon-Ho Kim·Sergei P. Kulik·Yanhua Shih
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Abstract

We report a quantum interference and imaging experiment which quantitatively demonstrates that Einstein-Podolsky-Rosen (EPR) type entangled two-photon states exhibit both momentum-momentum and position-position correlations, stronger than any classical correlation. The measurements show indeed that the uncertainties in the sum of momenta and in the difference of positions of the entangled two-photon satisfy both EPR inequalities D(k1+k2)<min(D(k1),D(k2)) and D(x1-x2)<min(D(x1),D(x2)). These two inequalities, together, represent a non-classicality condition. Our measurements provide a direct way to distinguish between quantum entanglement and classical correlation in continuous variables for two-photons/two photons systems.

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Milena D'Angelo, Yoon-Ho Kim, Sergei P. Kulik, Yanhua Shih. 2004-01-21. Identifying entanglement using quantum "ghost" interference and imaging. https://doi.org/10.1103/physrevlett.92.233601

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