Nonlinear Breit-Wheeler process in short laser double pulses

The nonlinear (strong-field) Breit-Wheeler e+e− pair production by a probe photon traversing two consecutive short and ultrashort (subcycle) 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 subcycle pulses and decreases rapidly with increasing width of the individual pulses.