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arXiv · 1301.2090

An extremely low-noise heralded single-photon source: a breakthrough for quantum technologies

G. Brida·I. P. Degiovanni·M. Genovese·F. Piacentini·P. Traina·A. Della Frera·A. Tosi·A. Bahgat Shehata·C. Scarcella·A. Gulinatti·M. Ghioni·S. V. Polyakov·A. Migdall·A. Giudice
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Abstract

Low noise single-photon sources are a critical element for quantum technologies. We present a heralded single-photon source with an extremely low level of residual background photons, by implementing low-jitter detectors and electronics and a fast custom-made pulse generator controlling an optical shutter (a LiNbO3 waveguide optical switch) on the output of the source. This source has a second-order autocorrelation g^{(2)}(0)=0.005(7), and an "Output Noise Factor" (defined as the ratio of the number of noise photons to total photons at the source output channel) of 0.25(1)%. These are the best performance characteristics reported to date.

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G. Brida, I. P. Degiovanni, M. Genovese, F. Piacentini, P. Traina, A. Della Frera, A. Tosi, A. Bahgat Shehata, C. Scarcella, A. Gulinatti, M. Ghioni, S. V. Polyakov, A. Migdall, A. Giudice. 2013-01-10. An extremely low-noise heralded single-photon source: a breakthrough for quantum technologies. https://doi.org/10.1063/1.4768288

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