Simulations of laser plasma instabilities using a particle-mesh method

Abstract

A physical model is presented for the study of parametric instabilities in inertial confinement fusion (ICF), which considers the coupling of the incident and scattered electromagnetic waves with plasma electrons and ions. Specially, this model is solved numerically with the particle-mesh method, where the plasma is represented by macro-particles both for electrons and ions, and the velocity and position of each macro-particle are numerically updated by using the particle-mesh method. The developed particle-mesh code in one-dimensional geometry (PM1D) is utilized to study the development of parametric instabilities at the nonlinear stages, where electron plasma wave breaking, particle trapping, hot electron generation and density cavity formation can occur. Particle-in-cell (PIC) simulations are carried out to verify this PM1D code. By comparison, it is found that this PM1D code is able to capture the kinetic effects and precisely describe the developments of parametric instabilities at nonlinear stages as the PIC simulations while saving the computation time obviously. Furthermore, a test simulation of the stimulated Raman scattering evolution up to 200 ps verifies the robustness of this PM1D code.