Two-dimensional particle-in-cell simulation of small-scale laser–plasma interactions with laser-produced plasma jets

Abstract

In inertial fusion for energy, bunches of small-scale filaments were observed in previous precise experiments with high spatial and temporal resolution in an average irradiance of ∼1013 W/cm2. This phenomenon is largely attributed to practical extremely nonuniform laser spots and inhomogeneous laser-produced plasmas. Comparing results of 2D particle-in-cell simulations with inhomogeneous and transversely homogeneous boundary conditions, we studied the influences of plasma jets on small-scale laser–plasma interactions. The facilitative effect of jets on the formation of light filaments, enhancing effect of jets on intensity of light filaments and 3ω0/2 harmonic emissions, and dynamic changes of filaments and 3ω0/2 harmonic emissions were observed. When the power density of incident light increases, the generation zone of the two-plasmon decay extends due to the dense electron walls formed by ponderomotive forces on the surrounding area of filaments. All the observations and preset boundary conditions proved to be well supported by some previous directly observed experimental results.