Shock pressure enhancement in plane-layered targets through laser-induced shock waves

Abstract

The pressure enhancement due to impedance-matching at the interface between the two-step layered targets has been well studied and established technique for EOS measurement of materials in laser driven shock wave experiments. A detailed numerical simulation study of shock wave propagation through Al standard material in laser driven shock wave experiments was performed using a 1-D radiation hydrodynamic code MULTI. The definitive role of mesh thickness was noticed. The experimental results of shock pressure enhancement in Al-Cu and Al-Au, layered targets corroborated with the numerical simulation results. Simulations were subsequently extended to plane-layered targets such as CH-Al, CH-Cu an CH-Au targets. It is shown that with proper tailoring of laser and target parameters, shock pressures in the range of up to 30 to 50 Mbar could be achieved with relatively moderate intensity lasers (IL = 6 - 8x1013 W/cm2; Pulse FWHM 600 - 800 ps). The numerical simulations also enumerate appropriate conditions to maintain the steadiness of shock waves with minimal preheat effect.