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arXiv · 0811.3612

Photon-Photon Entanglement with a Single Trapped Atom

B. Weber·H. P. Specht·T. Mueller·J. Bochmann·M. Muecke·D. L. Moehring·G. Rempe
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Abstract

An experiment is performed where a single rubidium atom trapped within a high-finesse optical cavity emits two independently triggered entangled photons. The entanglement is mediated by the atom and is characterized both by a Bell inequality violation of S=2.5, as well as full quantum-state tomography, resulting in a fidelity exceeding F=90%. The combination of cavity-QED and trapped atom techniques makes our protocol inherently deterministic - an essential step for the generation of scalable entanglement between the nodes of a distributed quantum network.

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B. Weber, H. P. Specht, T. Mueller, J. Bochmann, M. Muecke, D. L. Moehring, G. Rempe. 2008-11-21. Photon-Photon Entanglement with a Single Trapped Atom. https://doi.org/10.1103/physrevlett.102.030501

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