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arXiv · 1102.0484

Atom-Resonant Heralded Single Photons by Interaction-Free Measurement

Florian Wolfgramm·Yannick A. de Icaza Astiz·Federica A. Beduini·Alessandro Cere·Morgan W. Mitchell
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Abstract

We demonstrate the generation of rubidium-resonant heralded single photons for quantum memories. Photon pairs are created by cavity-enhanced down-conversion and narrowed in bandwidth to 7 MHz with a novel atom-based filter operating by "interaction-free measurement" principles. At least 94% of the heralded photons are atom-resonant as demonstrated by a direct absorption measurement with rubidium vapor. A heralded auto-correlation measurement shows $g_c^{(2)}(0)=0.040 \pm 0.012$, i.e., suppression of multi-photon contributions by a factor of 25 relative to a coherent state. The generated heralded photons can readily be used in quantum memories and quantum networks.

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Florian Wolfgramm, Yannick A. de Icaza Astiz, Federica A. Beduini, Alessandro Cere, Morgan W. Mitchell. 2011-02-02. Atom-Resonant Heralded Single Photons by Interaction-Free Measurement. https://doi.org/10.1103/physrevlett.106.053602

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