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Highly efficient heralding of entangled single photons



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


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.
Optics Express


transition edge sensors, single photon detection, photon heralding, Bell inequality


Ramelow, S. , Mech, A. , Giustina, M. , Groeblacher, S. , Wieczorek, W. , Lita, A. , Calkins, B. , Gerrits, T. , Nam, S. , Zeilinger, A. and Ursin, R. (2013), Highly efficient heralding of entangled single photons, Optics Express, [online], (Accessed May 27, 2024)


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Created March 10, 2013, Updated October 12, 2021