Generation of rapidly varying voltage and current pulses upon exposure of an atmospheric target to a train of laser pulses

The generation of voltage and current pulses upon exposure of a gaseous target to a laser pulse train under different focusing conditions and different gas pressures is studied. It is shown that, under atmospheric pressures, the current and voltage pulses appear upon repeated laser exposures; this phenomenon is associated with the formation of a low-density heated gas layer at the target surface, the expansion of which takes place during times commensurate with the period between the laser train pulses. The rapid variability of the current and voltage pulse response to the laser exposure was recorded making it possible to reproduce laser radiation modulation with frequencies greater than about 30 MHz.