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arXiv · 2510.10707

Automated discovery of high-dimensional multipartite entanglement with photons that never interacted

Sören Arlt·Mario Krenn·Xuemei Gu
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Abstract

Quantum entanglement across spatially separated network nodes is conventionally established through the distribution of photons from a common source or via entanglement swapping that relies on Bell-state measurements and pre-shared entanglement. Path identity, where the emission origins of photons from different sources are made indistinguishable, offers an alternative route. We show that this mechanism enables complex multipartite, high-dimensional, and even logical entanglement between remote nodes whose photons never interacted. Our schemes require neither direct photon interaction, pre-shared entanglement, nor Bell-state measurements, highlighting a distinct resource for distributed quantum communication and computation. All of the solutions were discovered automatically using highly efficient computational design tools, indicating the potential for scientific inspiration from computational algorithms.

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Sören Arlt, Mario Krenn, Xuemei Gu. 2025-10-12. Automated discovery of high-dimensional multipartite entanglement with photons that never interacted. https://arxiv.org/abs/2510.10707

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