Design of laser pulse shapes and target structures by random optimization for direct-drive inertial confinement fusion

Abstract

Quasi-isentropic compression is required for inertial confinement fusion (ICF) to compress the target to a high density and high temperature status, where to match the laser pulse shape and target structure is of great significance to the implosion. However, many parameters for the laser pulse shape and the target structure should be optimized in order to realize such match. In this paper, the drive laser pulse and the target structure are designed using a random optimization method for a direct-drive ICF implosion driven by a 358.40 kJ laser pulse. This method can quickly optimize the laser pulse and target structure parameters for an efficient quasi-isentropic compression of the plasmas, leading to an areal density of 9.30% higher than that given by the hydrodynamic scaling. A correlation matrix is also constructed to analyze the correlation between the parameters. This provides a reference for further optimization and improvement. The method should have potential applications in the target design for future ICF experiments.