Quantum advantage for single-photon state characterization

Abstract:We propose a multiphoton interference protocol that characterizes the pairwise overlaps of the internal modes of single photons more efficiently than pairwise Hong-Ou-Mandel characterization experiments. We experi mentally implement this protocol to characterize three photons. We show that our implementation of the char acterization protocol outperforms the pairwise Hong-Ou-Mandel characterization, even if the Hong-Ou-Mandel characterization would have been performed in a noiseless, perfect experiment. We demonstrate this via the Fisher information matrix. Surprisingly, this advantage persists at arbitrary nonzero transmission, demonstrat ing the viability of this protocol for real-world characterization of single photons.

arXiv:2512.04903 [quant-ph]

(or arXiv:2512.04903v2 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2512.04903 Focus to learn more arXiv-issued DOI via DataCite

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