Laser ionization from full electric field

[MaxThevenet]

The current implementation of laser ionization directly calculates the ionization probability and resulting momentum from the AC model, i.e., averaging over the laser period that is typically not resolved by the longitudinal resolution. While still default, it would be useful to also allow for calculation of these properties from the actual electric field and vector potential. The laser vector potential $a$ can be obtained from its envelope $a_{env}$ as $a = Re(a_{env} e^{i k_0 \zeta})$.