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Atom-Photon Entanglement

Juergen Volz·Markus Weber·Daniel Schlenk·Wenjamin Rosenfeld·Johannes Vrana·Karen Saucke·Christian Kurtsiefer·Harald Weinfurter
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Abstract

We report the observation of entanglement between a single trapped atom and a single photon at a wavelength suitable for low-loss communication over large distances, thereby achieving a crucial step towards long range quantum networks. To verify the entanglement we introduce a single atom state analysis. This technique is used for full state tomography of the atom-photon qubit-pair. The detection efficiency and the entanglement fidelity are high enough to allow in a next step the generation of entangled atoms at large distances, ready for a final loophole-free Bell experiment.

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Juergen Volz, Markus Weber, Daniel Schlenk, Wenjamin Rosenfeld, Johannes Vrana, Karen Saucke, Christian Kurtsiefer, Harald Weinfurter. 2005-11-18. Atom-Photon Entanglement. https://arxiv.org/abs/quant-ph/0511183

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