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Synchronized Independent Narrow-band Single Photons and Efficient Generation of Photonic Entanglement

Zhen-Sheng Yuan·Yu-Ao Chen·Shuai Chen·Bo Zhao·Markus Koch·Thorsten Strassel·Yong Zhao·Gan-Jun Zhu·Jörg Schmiedmayer·Jian-Wei Pan
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Abstract

We create independent, synchronized single-photon sources with built-in quantum memory based on two remote cold atomic ensembles. The synchronized single photons are used to demonstrate efficient generation of entanglement. The resulting entangled photon pairs violate a Bell's Inequality by 5 standard deviations. Our synchronized single photons with their long coherence time of 25 ns and the efficient creation of entanglement serve as an ideal building block for scalable linear optical quantum information processing.

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Zhen-Sheng Yuan, Yu-Ao Chen, Shuai Chen, Bo Zhao, Markus Koch, Thorsten Strassel, Yong Zhao, Gan-Jun Zhu, Jörg Schmiedmayer, Jian-Wei Pan. 2007-05-05. Synchronized Independent Narrow-band Single Photons and Efficient Generation of Photonic Entanglement. https://doi.org/10.1103/physrevlett.98.180503

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