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arXiv · 2111.15308

Reducing $g^{(2)}(0)$ of a parametric down-conversion source via photon-number resolution with superconducting nanowire detectors

S. Sempere-Llagostera·G. S. Thekkadath·R. B. Patel·W. S. Kolthammer·I. A. Walmsley
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Abstract

Multiphoton contributions pose a significant challenge for the realisation of heralded single-photon sources (HSPS) based on nonlinear processes. In this work, we improve the quality of single photons generated in this way by harnessing the photon-number resolving (PNR) capabilities of commercial superconducting nanowire single-photon detectors (SNSPDs). We report a $13 \pm 0.4 \%$ reduction in the intensity correlation function $g^{(2)}(0)$ even with a collection efficiency in the photon source of only $29.6\%$. Our work demonstrates the first application of the PNR capabilities of SNSPDs and shows improvement in the quality of an HSPS with widely available technology.

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BibTeXRIS

S. Sempere-Llagostera, G. S. Thekkadath, R. B. Patel, W. S. Kolthammer, I. A. Walmsley. 2021-11-30. Reducing $g^{(2)}(0)$ of a parametric down-conversion source via photon-number resolution with superconducting nanowire detectors. https://doi.org/10.1364/oe.450172

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