TY - JOUR AU - Faleiro, R. AU - Pavao, R. AU - Costa, H. A. S. AU - Hiller, B. AU - Blin, A. H. AU - Sampaio, M. PY - 2020 DA - 2020// TI - Perturbative approach to entanglement generation in QFT using the S matrix T2 - J. Phys. A JO - Journal of Physics A SP - 365301 - 19pp VL - 53 IS - 36 PB - Iop Publishing Ltd KW - S-matrix KW - entanglement KW - QFT KW - cross-section AB - We compute the variation of the von Neumann (VN) entropy Delta Sbetween the asymptoticinandoutmomenta modes of a real scalar field A, when elastically scattered against the modes of another scalar field B. This is done to see how the entanglement between the two fields' momenta changes under the scattering procedure. The calculation is separated into two case studies, one where the fields' asymptoticinstates are separable, and another where they are arbitrarily entangled. We perform a perturbative calculation to one loop order in the separable case, and verify that Delta Schanges in a non-trivial way when we vary the momentum of the incoming field modes and/or the coupling of the theory. Finally, also in the separable case, we show an explicit dependence between Delta Sand the cross-section of the collision, consistent with perturbation theory. SN - 1751-8113 UR - https://arxiv.org/abs/1607.01715 UR - https://doi.org/10.1088/1751-8121/aba214 DO - 10.1088/1751-8121/aba214 LA - English N1 - WOS:000563486000001 ID - Faleiro_etal2020 ER -