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arXiv:2603.12830 · Journal of High Energy Physics

Quantum entanglement and Bell nonlocality in top-quark pair production at a photon linear collider

Seong Youl Choi, Dong Woo Kang, Jae Sik Lee, Chan Beom Park

Published Oct 1, 2026• 0 citations
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Abstract

A bstract A photon linear collider, the two-photon collision mode of an e + e − linear collider, uses high-energy laser photons backscattered off the incoming electrons and positrons. The colliding-photon polarization is fully controllable through the polarizations of the initial electron and positron beams and laser photons. We investigate the impact of colliding-photon polarization on the observability of quantum entanglement in top-quark pair production at a photon linear collider. Constructing the spin density matrix of the $$t\overline{t }$$ two-qubit system from the helicity amplitudes, we demonstrate that a photon linear collider is an ideal machine to probe quantum entanglement and Bell nonlocality across the broad phase space of the process.

DOI
10.1007/jhep10(2026)017

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