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arXiv · 2306.13646

Perfect single-photon sources

Sana Khalid·Fabrice P. Laussy
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Abstract

We introduce the "gapped coherent state" in the form of a single-photon source (SPS) that consists of uncorrelated photons as a background, except that we demand that no two photons can be closer in time than a time gap $t_\mathrm{G}$. While no obvious quantum mechanism is yet identified to produce exactly such a photon stream, a numerical simulation is easily achieved by first generating an uncorrelated (Poissonian) signal and then for each photon in the list, either adding such a time gap or removing all successive photons that are closer in time from any photon that is kept than $t_\mathrm{G}$. We study the statistical properties of such a hypothetical signal, which exhibits counter-intuitive features. This provides a neat and natural connection between continuous-wave (stationary) and pulsed single-photon sources, with also a bearing on what it means for such sources to be perfect in terms of single-photon emission.

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Sana Khalid, Fabrice P. Laussy. 2023-06-23. Perfect single-photon sources. https://arxiv.org/abs/2306.13646

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