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Ultra-bright source of polarization-entangled photons

Paul G. Kwiat·Edo Waks·Andrew G. White·Ian Appelbaum·Philippe H. Eberhard
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Abstract

Using the process of spontaneous parametric down conversion in a novel two-crystal geometry, one can generate a source of polarization-entangled photon pairs which is orders of magnitude brighter than previous sources. We have measured a high level of entanglement between photons emitted over a relatively large collection angle, and over a 10-nm bandwidth. As a demonstration of the source intensity, we obtained a 242-$σ$ violation of Bell's inequalities in less than three minutes.

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Paul G. Kwiat, Edo Waks, Andrew G. White, Ian Appelbaum, Philippe H. Eberhard. 1999-05-22. Ultra-bright source of polarization-entangled photons. https://doi.org/10.1103/physreva.60.r773

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