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arXiv · 1211.5059

Highly efficient heralding of entangled single photons

Sven Ramelow·Alexandra Mech·Marissa Giustina·Simon Groeblacher·Witlef Wieczorek·Adriana Lita·Brice Calkins·Thomas Gerrits·Sae Woo Nam·Anton Zeilinger·Rupert Ursin
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Abstract

Single photons are an important prerequisite for a broad spectrum of quantum optical applications. We experimentally demonstrate a heralded single-photon source based on spontaneous parametric down-conversion in collinear bulk optics, and fiber-coupled bolometric transition-edge sensors. Without correcting for background, losses, or detection inefficiencies, we measure an overall heralding efficiency of 83 %. By violating a Bell inequality, we confirm the single-photon character and high-quality entanglement of our heralded single photons which, in combination with the high heralding efficiency, are a necessary ingredient for advanced quantum communication protocols such as one-sided device-independent quantum key distribution.

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Sven Ramelow, Alexandra Mech, Marissa Giustina, Simon Groeblacher, Witlef Wieczorek, Adriana Lita, Brice Calkins, Thomas Gerrits, Sae Woo Nam, Anton Zeilinger, Rupert Ursin. 2012-11-22. Highly efficient heralding of entangled single photons. https://doi.org/10.1364/oe.21.006707

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