Three-dimensional kinetic simulations of the collective processes in beam-plasma interaction*

Electron beam-plasmas have long been a topic of interest for the study of nonlinear wave-wave interactions and turbulence. Understanding these collective processes is important for the design of low-temperature, low-pressure discharge devices for industry. To date, simulations of electron beam-plasmas have mostly been performed with 2D codes. The limitations of these 2D simulations have, however, never been tested. Therefore, in this study, we make use of a GPU-accelerated code, LTP-PIC (Low Temperature Plasma Particle-In-Cell), to perform 3D fully kinetic simulations and investigate the collective effects of a mono-energetic electron beam propagating through a cold plasma. The classical theories describing the saturation of streaming instabilities and the Langmuir collapse are examined, for the first time, in three-dimensional simulations. By comparing the 2D and 3D simulation results, we study the influence of dimensionality on the Langmuir turbulence. The correlation between the anomalous electron transport and the Langmuir turbulence is also analyzed.