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arXiv · 2512.04903

Quantum advantage for single-photon state characterization

S. N. van den Hoven·M. C. Anguita·S. Marzban·J. J. Renema
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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.

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S. N. van den Hoven, M. C. Anguita, S. Marzban, J. J. Renema. 2025-12-04. Quantum advantage for single-photon state characterization. https://doi.org/10.1103/g28d-jzgj

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