Genuine tripartite entanglement in Bhabha scattering with an entangled spectator particle

TL;DR

This paper demonstrates that Bhabha scattering in QED can generate genuine tripartite entanglement among an electron, positron, and spectator electron, with entanglement properties influenced by scattering momentum and initial entanglement.

Contribution

It reveals how QED scattering processes can produce and control genuine tripartite entanglement, providing insights for quantum information applications in fundamental physics.

Findings

Scattering can drive the system into a genuine tripartite entangled state.

Initial entanglement and scattering momentum are key resources for GTE generation.

Monogamy constraints are relaxed in the non-relativistic regime, enhancing quantum correlation shareability.

Abstract

From the perspective of quantum information science, we investigate tree-level Bhabha scattering between an incident electron $A$ and a positron B, where $B$ is initially entangled with a spectator electron $C$, which does not participate in the scattering interaction.We find that the quantum electrodynamics (QED) scattering between $A$ and $B$ can drive the global $ABC$ system into a genuine tripartite entangled (GTE) state. Using four canonical tripartite entanglement metrics, we systematically characterize and quantify the GTE of the composite system, and demonstrate that the scattering momentum of the $A$-$B$ pair and the initial $B$-$C$ entanglement are the key resources governing GTE generation.We further analyze the monogamy of quantum correlations, which imposes fundamental constraints on the shareability of quantum resources in multipartite systems. Specifically, we systematically study the monogamy relations for the squared entanglement of formation and squared quantum discord in our scattering model, and find that monogamy constraints are markedly relaxed in the non-relativistic regime, enabling enhanced shareability of quantum correlations across the three particles. This work uncovers novel quantum correlation properties of fundamental QED scattering processes, and provides direct theoretical guidance for the development of QED-based quantum information processing protocols.