Laser induced shock pressure multiplication in multi layer thin foil targets

Abstract

The impedance mismatch technique has been used for shock pressure amplification in two- and three-layer thin planar foil targets. Numerical simulation results using one-dimensional radiation hydrocode MULTI in two-layer targets consisting of Al-Au and Al-Cu and three-layer target consisting of plastic-Al-Au and foam-Al-Au, respectively, are presented. These results show a pressure enhancement up to 25 and 29 Mbar for plastic-Al-Au and foam-Al-Au targets, respectively, from an initial pressure of 7 Mbar in the reference material using laser intensity of 5 × 10¹³ W cm^-2 at 1.064 µm. This enhancement is more as compared with 18 and 22 Mbar found in plastic-Au and foam-Au two-layer targets, respectively. Results of laser driven shock wave experiments for equation of state (EOS) studies of Au and Cu in two-layer target are also presented. A Nd : YAG laser chain (2 J, 1.06 µm wavelength, 200 ps pulse FWHM) is used for generating shocks in the planar Al foils and Al-Au (or Al-Cu) layered targets. The EOS of Au and Cu in the pressure range of 9-14 Mbar obtained shows remarkable agreement with the simulation results and with experimental data of other laboratories and SESAME data.