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arXiv · 2502.11631

Advancing the heralded photon-number-state characterization by understanding the interplay of experimental settings

Daniel Borrero Landazabal·Kaisa Laiho
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Abstract

We theoretically explore the properties of heralded number states including up to three photons that are generated from single-mode twin beams. We investigate the effects of different parameters involved in the state preparation by using the fidelity, normalized second-order factorial moment of photon number for the heralded state $(g^{(2)}_h)$, and photon-number parity as figures of merit. Especially, the photon-number parity offers a practical and robust tool for inferring the target state quality by capturing the contamination of all undesired photon-number contributions. We focus on expressing our results in terms of experimentally easily accessible parameters such as the coincidences-to-accidentals ratio and the detection efficiencies. Our results identify the optimal parameter regions for generating high quality photon-number states by heralding and provide useful insights for advancing their use in quantum technologies.

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Daniel Borrero Landazabal, Kaisa Laiho. 2025-05-28. Advancing the heralded photon-number-state characterization by understanding the interplay of experimental settings. https://doi.org/10.1088/1367-2630%2Faddc11

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