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arXiv · 0808.3538

Long-distance atom-photon entanglement

W. Rosenfeld·F. Hocke·F. Henkel·M. Krug·J. Volz·M. Weber·H. Weinfurter
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Abstract

We report the observation of entanglement between a single trapped atom and a single photon at remote locations. The degree of coherence of the entangled atom-photon pair is verified via appropriate local correlation measurements, after communicating the photon via an optical fiber link of 300 m length. In addition we measured the temporal evolution of the atomic density matrix after projecting the atom via a state measurement of the photon onto several well defined spin states. We find that the state of the single atom dephases on a timescale of 150 $μ$s, which represents an important step toward long-distance quantum networking with individual neutral atoms.

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W. Rosenfeld, F. Hocke, F. Henkel, M. Krug, J. Volz, M. Weber, H. Weinfurter. 2008-08-26. Long-distance atom-photon entanglement. https://doi.org/10.1103/physrevlett.101.260403

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