Effect of field ionization on interaction of an intense subpicosecond laser pulse with foils

The effect of transient ionization in an intense, short laser pulse irradiated foil is investigated via a simulation based on the collisional particle-in-cell method coupled with the atomic kinetics. A strong electric field induced by superthermal electrons causes significant plasma ionization at the rear surface of the target. The plasma induced field ionization is found to dominate the production of the multiple-charged ions at the rear surface of the foil, which are accelerated forward up to multi mega electron volts by irradiation of a subpicosecond laser pulse with intensities from 10(19) to 10(20) W/cm(2). (C) 2000 American Institute of Physics. [S1070-664X(00)01405-1].