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Experimental Realization of Entanglement Concentration and A Quantum Repeater

Zhi Zhao·Tao Yang·Yu-Ao Chen·An-Ning Zhang·Jian-Wei Pan
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Abstract

We report an experimental realization of entanglement concentration using two polarization-entangled photon pairs produced by pulsed parametric down-conversion. In the meantime, our setup also provides a proof-in-principle demonstration of a quantum repeater. The quality of our procedure is verified by observing a violation of Bell's inequality by more than 5 standard deviations. The high experimental accuracy achieved in the experiment implies that the requirement of tolerable error rate in multi-stage realization of quantum repeaters can be fulfilled, hence providing a practical toolbox for quantum communication over large distances.

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Zhi Zhao, Tao Yang, Yu-Ao Chen, An-Ning Zhang, Jian-Wei Pan. 2003-01-22. Experimental Realization of Entanglement Concentration and A Quantum Repeater. https://doi.org/10.1103/physrevlett.90.207901

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