Description
We investigate spin effects in the momentum distributions of created particles in the dynamical Schwinger process. For this purpose, we develop the S-matrix formalism describing the Schwinger pair production in the presence of a time-dependent electric field for the Dirac [1] and for the Klein-Gordon [2] particles. This allows us to compare the momentum distributions of created spinor and scalar pairs.
Our analysis demonstrates the appearance of vortex structures in the momentum distributions of both spinor and scalar pairs, when a circularly polarized time-dependent electric field interacts with the QED vacuum [1,2]. The reason is that vortices are signatures of nonvanishing angular momentum, which is transferred from the driving electric field to the particles. As we show, the angular momentum gets redistributed differently for the spinor and for the scalar pairs. Thus, influencing their momentum distributions. In our numerical examples, we observe creation of vortex and anti-vortex structures with elementary topological charges. As we test, the number of those structures complies with the angular momentum conservation principle.
[1] M. M. Majczak, K. Krajewska, J. Z. Kamiński, and A. Bechler, Phys. Rev. D 110, 116025 (2024).
[2] W. Śmiałek, M. M. Majczak, A. Bechler, J. Z. Kamiński, C. Müller, and K. Krajewska, in preparation (2025).
E-mail address: Mateusz.Majczak@fuw.edu.pl
