Integrative simulation of a 2 cm electron cyclotron resonance ion source with full particle-in-cell method

Abstract

A two-dimensional full particle-in-cell model is developed to simulate the operation process of a 2 cm electron cyclotron resonance ion thruster. The simulation regions include the discharge chamber, grid system, and plume, and the processes of neutral gas injection, plasma discharge, and ion beam extraction are simulated continuously. Neutrals are treated as particles and managed through an adaptive particle management algorithm. The collisions between charged and neutral particles are approached by the method of combining the Monte Carlo and directly simulation Monte Carlo collisions. The integrative simulation provides a global perspective to learn the gridded ion thruster, such as the Child-Langmuir sheath, acceleration grid erosion, plasma bridge, and so on. In this paper, the response of the plasma system to the accelerating voltage is analyzed, which is related to the bulk plasma, antenna floating voltage, and Child-Langmuir sheath. Besides, an ion density wave is observed in plume, which will increase the current of acceleration grid and cause ion backflow.