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arXiv · 2102.08419

Estimating the photon-number distribution of photonic channels with realistic devices and applications in photonic quantum information processing

Emilien Lavie·Ignatius William Primaatmaja·Wen Yu Kon·Chao Wang·Charles Ci Wen Lim
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Abstract

Characterising the input-output photon-number distribution of an unknown optical quantum channel is an important task for many applications in quantum information processing. Ideally, this would require deterministic photon-number sources and photon-number-resolving detectors, but these technologies are still work-in-progress. In this work, we propose a general method to rigorously bound the input-output photon number distribution of an unknown optical channel using standard optical devices such as coherent light sources and non-photon-number-resolving detectors/homodyne detectors. To demonstrate the broad utility of our method, we consider the security analysis of practical quantum key distribution systems based on calibrated single-photon detectors and an experimental proposal to implement time-correlated single photon counting technology using homodyne detectors instead of single-photon detectors.

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Emilien Lavie, Ignatius William Primaatmaja, Wen Yu Kon, Chao Wang, Charles Ci Wen Lim. 2021-02-16. Estimating the photon-number distribution of photonic channels with realistic devices and applications in photonic quantum information processing. https://doi.org/10.1103/physrevapplied.16.034020

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