https://doi.org/10.1140/epja/s10050-026-01791-x
Regular Article - Theoretical Physics
Investigation of entanglement in pure final polarization states from neutron–deuteron elastic scattering and exclusive deuteron breakup
M. Smoluchowski Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30348, Kraków, Poland
a
This email address is being protected from spambots. You need JavaScript enabled to view it.
Received:
19
November
2025
Accepted:
12
January
2026
Published online:
3
February
2026
Abstract
We investigate the pure polarization states of the outgoing neutron–deuteron (nd) pair in elastic polarized neutron–polarized deuteron scattering, as well as the pure polarization states of the three free nucleons (nnp) produced in the corresponding deuteron breakup reaction. Our aim is to provide clear evidence of entanglement in their spin degrees of freedom. These final states can be generated from pure spin states of the incoming nd system, where both the neutron and the deuteron are strongly polarized by maximizing the occupation of a specific magnetic substate. To fully characterize the final configurations, we compute the corresponding spin density matrices using the high-precision CD-Bonn nucleon–nucleon potential. Among these pure final spin states, we identify strongly entangled, Bell-like states that include at most small admixtures of components diminishing entanglement.
Copyright comment Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
Communicated by Arnau Rios Huguet.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2026
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
