The non-linear (strong-field) Breit-Wheeler e+e− pair production by a probe photon traversing two consecutive short and ultra short (sub-cycle) laser pulses is considered within a QED framework. The temporal shape of the pulses and the distance between them are essential for the differential cross section as a function of the azimuthal angle distribution of the outgoing electron (positron). The found effect of a pronounced azimuthal anisotropy is important for sub-cycle pulses and decreases rapidly with increasing width of the individual pulses.
@article{arxiv.1807.04547,
title = {Non-linear Breit-Wheeler process in short laser double-pulses},
author = {A. I. Titov and B. Kampfer and H. Takabe},
journal= {arXiv preprint arXiv:1807.04547},
year = {2018}
}