Numerical analysis of ionization and plasmonic phenomena on gold nanodopes upon laser pulse irradiation

We investigate the dynamics of plasmonic phenomena on gold nanoparticles and ionization under irradiation by short infrared pulses with intensities ~4∙1015−4∙1017 W/cm². Numerical modeling of the interaction between laser radiation and the medium doped with nanoparticles (nanodopes) is conducted; various nanoparticles shapes are considered as resonant nanoantennas. A kinetic model is implemented with the EPOCH numerical software. The propagation of short pulses of infrared laser radiation of ≈0.1 ps duration in such doped matter and the dynamics of plasmon formation, its behavior in fields of various intensities and ionization are analyzed. The evolution of the electric field around dopes, of the plasmon and transfer of energy from wave to ions are studied. The momentum and energy of the resulting ionization products — protons, electrons and ions — are calculated. Plasmonic phenomena on nanoparticles of dipole, quadrupole, and spherical shapes and different sizes are explored. The comparative analysis is conducted for various shapes of dopes and various intensities of laser pulses, aiming to identify best resonating properties, plasmon life and increase of the energy of ioniza tion products in strong laser fields.