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arXiv · 2608.18030

Three-qubit entanglement in the Bethe-Heitler process

Haotian Cao·Yuxun Guo·Yoshitaka Hatta·Jakob Schoenleber
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Abstract

The familiar Bethe-Heitler process on the proton target $e+p\to e+p+\gamma$ is transformed into a laboratory for studying multiparticle entanglement. We discuss how bipartite and genuine tripartite entanglement between the final state electron, proton and photon are built up by successive $1\to 2$ and $2\to 2$ elementary interactions. We validate our argument by simulating events. Below 5 GeV center-of-mass energy, we identify more than 900 Greenberger-Horne-Zeilinger (GHZ) states and 1200 W states, each with a fidelty exceeding 99%.

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Haotian Cao, Yuxun Guo, Yoshitaka Hatta, Jakob Schoenleber. 2026-08-18. Three-qubit entanglement in the Bethe-Heitler process. https://arxiv.org/abs/2608.18030

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