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arXiv · 1705.01778

Fibre-integrated noise gating of high-purity heralded single photons

Robert J. A. Francis-Jones·Peter J. Mosley
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Abstract

We present an all-fibre source of high-purity heralded single photons with an integrated conditional optical gate that reduces uncorrelated noise by almost an order of magnitude. Generating photon pairs by four-wave mixing in photonic crystal fibre, we observe with the noise gate active a factor of 7 reduction in the rate of single counts in the heralded channel with no measurable drop in coincidence count rate. In contrast to electronic post-selection of coincidence events, the real reduction in the flux of unwanted photons is beneficial for example to avoid bleaching light-sensitive samples or in generating entangled states.

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Robert J. A. Francis-Jones, Peter J. Mosley. 2017-05-04. Fibre-integrated noise gating of high-purity heralded single photons. https://doi.org/10.1088/2040-8986%2Faa8880

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