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arXiv · 2607.25501

Automated discovery of high-probability heralded schemes for path-entangled states

Marcello Armezzani·Colin P. Lualdi·Xuemei Gu·Paul G. Kwiat·Mario Krenn
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Abstract

Entangled states of light lie at the heart of photonic quantum technologies, from distributed quantum communication to quantum-enhanced measurement and information processing. Their practical generation, however, remains constrained by the weak interactions between photons, which make the deterministic assembly of large multiphoton entangled states a central challenge in quantum optics. In this work, we use AI techniques to discover heralded linear-optical schemes for path-entangled states and show that the resulting solutions can be elevated from individual circuits to a new scalable family. This family contains previously known constructions as special cases while generally providing exponential and super-exponential improvements over those, and its extension to broader classes of target states shows how automated discovery can reveal transferable physical understanding. By presenting compact experimental proposals for large path-entangled states, our results provide both a theoretical advance in photonic heralding and a route towards a substantial leap in experimentally accessible multiphoton entanglement.

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Marcello Armezzani, Colin P. Lualdi, Xuemei Gu, Paul G. Kwiat, Mario Krenn. 2026-07-28. Automated discovery of high-probability heralded schemes for path-entangled states. https://arxiv.org/abs/2607.25501

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