Numerical modeling of laser tunneling ionization in explicit particle-in-cell codes

摘要

Methods for the calculation of laser tunneling ionization in explicit particle-in-cell codes used for modeling laser-plasma interactions are compared and validated against theoretical predictions. Improved accuracy is obtained by using the direct current form for the ionization rate. Multi level ionization in a single time step and energy conservation have been considered during the ionization process. The effects of grid resolution and number of macro-particles per cell are examined. Implementation of the ionization algorithm in two different particle-in-cell codes is compared for the case of ionization-based electron injection in a laser-plasma accelerator.