Investigation of entanglement in pure final polarization states from neutron-deuteron elastic ccattering and exclusive deuteron break

We investigate the pure polarization states of the outgoing neutron deuteron pair in elastic polarized neutron polarized deuteron scattering, as well as the pure polarization states of the three free nucleons 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.