Benchmarking semiclassical approaches to strong-field QED: Nonlinear Compton scattering in intense laser pulses
Journal article, 2018

The recoil associated with photon emission is key to the dynamics of ultrarelativistic electrons in strong electromagnetic fields, as found in high-intensity laser-matter interactions and astrophysical environments such as neutron star magnetospheres. When the energy of the photon becomes comparable to that of the electron, it is necessary to use quantum electrodynamics (QED) to describe the dynamics accurately. However, computing the appropriate scattering matrix element from strong-field QED is not generally possible due to multiparticle effects and the complex structure of the electromagnetic fields. Therefore, these interactions are treated semiclassically, coupling probabilistic emission events to classical electrodynamics using rates calculated in the locally constant field approximation. Here, we provide comprehensive benchmarking of this approach against the exact QED calculation for nonlinear Compton scattering of electrons in an intense laser pulse. We find agreement at the percentage level between the photon spectra, as well as between the models' predictions of absorption from the background field, for normalized amplitudes a0> 5. We discuss possible routes towards improved numerical methods and the implications of our results for the study of QED cascades.

Author

Tom Blackburn

Chalmers, Physics, Theoretical Physics

D. Seipt

Daresbury Laboratory

Lancaster University

S. S. Bulanov

Lawrence Berkeley National Laboratory

Mattias Marklund

Chalmers, Physics, Theoretical Physics

Physics of Plasmas

1070-664X (ISSN) 1089-7674 (eISSN)

Vol. 25 8 83108

Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Theoretical Chemistry

DOI

10.1063/1.5037967

More information

Latest update

8/29/2018