Enhancement of laser induced shock pressure in multilayer solid targets

Abstract

The impedance mismatch technique was used for shock pressure amplification in two layered planar foil targets. Numerical simulation results using one-dimensional~1D! radiation hydrocode MULTI in two layer target consisting of polyethylene~CH 2 ! n -aluminium~Al! and polyethylene~CH 2 ! n -gold~Au!, show a pressure enhancement of 12 and 18 Mbar, respectively~or a pressure jump of 1.64 and 2.54, respectively!, from initial pressure of 7 Mbar in the reference material~polyethylene! using laser intensity of 5 ϫ 10 13 Watts0cm 2 at 1.064 mm. The simulation data was also corroborated by experiments in our laboratory. Results of laser driven shock wave experiments for pressure enhancement studies in CH 2 -Al and CH 2 -Au targets are also presented. A Nd:YAG laser chain~2 J, 1.064 mm wavelength, 200 ps pulse duration FWHM! is used for generating shocks in the planar CH 2 foils of thickness varying from 4 to10 mm, and in two layered CH 2 -Al~or CH 2 -Au! targets with 8 mm CH 2 and 1.5 mm Al or Au .

Potential SiO2/CRF bilayer perturbation aerogel target for ICF hydrodynamic instability experiment

“…During the initial part of the implosion, as the capsule is compressed and accelerated inward, the interface between two adjacent layers is hydrodynamic instability which is seeded by interface roughness and grows via the Rayleigh-Taylor instability (RTI) [2,3]. In recent years, many different kinds of targets had been designed and fabricated to control and investigate the growth of RTI, such as single layer targets [4][5][6][7][8][9], dual-layer targets [10,11] and multilayer targets [12,13]. However, a little attention had been paid to bilayer aerogel target with perturbation patterns in the interface.…”