Characterization of electromagnetic pulse generated from plasma associated with laser filaments-excited aluminum alloy in air

Femtosecond laser filament-generated plasma can generate electromagnetic pulses (EMPs).These pulses may reduce the instrument’s precision, and, hence, influence the accuracy of theexperimental results. They may even cause widespread disruption by disabling of the electroniccontrol systems or distribution networks of power plants. This study investigated the characteristicsof EMPs generated from the interaction of filament-generated plasmas with a solid target in air. In thisstudy, ultrafast laser filamentation was used to produce plasma, which was focused on a 3 mm-thickaluminum (Al) alloy target for interaction, and the spatial distribution and main contributors of theEMPs were systematically and extensively studied. The results showed that the EMPs generatedfrom ultrafast laser filament interaction with the Al alloy target had the following characteristics: theEMP energy generated from laser filament interaction with solid targets is tens of times higher thanthat generated only from the femtosecond laser filament; the maximum EMP signals appeared ata 20–80detection angle. The relationship between the energy of EMPs and the width and energyof the laser pulses is presented and discussed. These findings are beneficial for gaining insight intothe EMP generation mechanism, spatial distribution, and transmission, and for providing moreinformation for the design of EMPs’ shielding.