Title:
Comparison of semiclassical and Wigner function methods in pair production in rotating fields

Abstract:
We present a comparison of two methods to compute the momentum spectrum and the Schwinger pair creation rate for pulsed rotating electric fields: one based upon the real-time Dirac-Heisenberg-Wigner (DHW) formalism and a semiclassical approximation based on a scattering ansatz. For the semiclassical method we propose to either perform numerical calculations or an additional approximation based on an analytical solution for the constant rotating field. We find that both numerical methods are complementary with respect to computation time as well as accuracy. The approximate method shows the same qualitative features while being computationally much faster. We additionally find that the unequal production of pairs in different spin states reported for constant rotating fields with the scattering method is in agreement with the Wigner function method.

Authors:
Alexander Blinne
Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena, Germany
Helmholtz-Institut Jena, Fröbelstieg 3, D-07743 Jena, Germany
Eckhard Trobel
ICRANet, Piazzale della Repubblica 10, 65122 Pescara, Italy
Dipartimento di Fisica, Università di Roma “La Sapienza,” Piazzale Aldo Moro 5, 00185 Rome, Italy
Université de Nice Sophia Antipolis, 28 Avenue de Valrose, 06103 Nice Cedex 2, France