Entanglement generation between two colliding particles

Abstract

Entanglement generation in the one-dimensional collision of two initially uncorrelated spin-1/2 particles is analyzed. It is assumed that the colliding particles interact with each other through a delta potential with a spin-spin coupling strength. Two different approaches are followed. In the first approach, the colliding particles are described by plane waves and in the second one by Gaussian wave packets. It is shown that the collision process create a final state which may be entangled in both momentum and spin spaces. The magnitude of the created entanglement is a function of the potential strength, the initial spin state and the initial momentum of the particles. By changing the initial spin state of the system, an entanglement exchange occurs between the k and spin spaces. Also, the present wave-packet analysis demonstrates, somewhat surprisingly, that initial widths of the wave packets describing the colliding particles play but a minor role for the entanglement generation process. © 2014 EDP Sciences, Società Italiana di Fisica, Springer-Verlag.