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arXiv · 0706.2327

A Robust Atom-Photon Entanglement Source for Quantum Repeaters

Shuai Chen·Yu-Ao Chen·Bo Zhao·Zhen-Sheng Yuan·Joerg Schmiedmayer·Jian-Wei Pan
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Abstract

We demonstrate a novel way to efficiently and very robust create an entanglement between an atomic and a photonic qubit. A single laser beam is used to excite one atomic ensemble and two different spatial modes of scattered Raman fields are collected to generate the atom-photon entanglement. With the help of build-in quantum memory, the entanglement still exists after 20.5 $μ$s storage time which is further proved by the violation of CHSH type Bell's inequality. Our entanglement procedure is the building block for a novel robust quantum repeater architecture [Zhao et al, Phys. Rev. Lett. 98, 240502 (2007)]. Our approach can be easily extended to generate high dimensional atom-photon entanglements.

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Shuai Chen, Yu-Ao Chen, Bo Zhao, Zhen-Sheng Yuan, Joerg Schmiedmayer, Jian-Wei Pan. 2007-06-15. A Robust Atom-Photon Entanglement Source for Quantum Repeaters. https://doi.org/10.1103/physrevlett.99.180505

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