Shock-Wave Pressure Transfer to a Solid Target with Porous Absorber of High-Power Laser Pulse

Results of experiments aimed at amplification of the pressure of laser-induced shock wave on the passage from low- to high-density target material via vacuum gap are presented. During the action of nanosecond laser pulse of terawatt power on plane composite targets comprising a layer of laser radiation absorber of low-density (0.01–0.025 g/cm 3 ) spaced by vacuum gap from a layer of aluminum, the shock-wave velocity in aluminum reached 25–29 km/s and a pressure jump at the aluminum layer boundary was 1.2–1.5 times as large as that observed in experiments on the cumulative transition of laser-induced shock wave into a solid. The obtained experimental data are compared to results of the numerical calculations performed using hydrodynamic programs in which the shock-wave generation and propagation was modeled with allowance for the interaction of laser pulses with partly homogenized plasma of the porous material. Based on the results of experiments, numerical calculations, and their theoretical analysis, the efficiency of using low-density porous media in the targets intended for their equation of state investigations and inertial confinement fusion ignition is considered.