Physical model of the formation of a low-temperature dense plasma during the irradiation of a target by a picosecond laser pulse

Results are presented from numerical simulations of the breakdown of a dense noble gas by the electrons of a boundary layer that forms during the irradiation of a metal target by a high-power picosecond laser pulse. It is shown that, when the electric field of the boundary layer is taken into account, the density of the seed electrons near the target surface increases substantially, so that the ionization process occurs much faster. The dependence of the time of the onset of breakdown on the electric field of the incident wave and on the concentration of gas atoms is calculated.