Plasma simulation to analyze velocity distribution characteristics of pseudospark-sourced electron beam?

• 作者: Bin Wang Che Xu Chen-Fei Hu Hai-Long Li Lin Meng Mao-Yan Wang Yong Yin
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2020,（10）
• 所属期刊栏目: PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
• 页码范围: 433-438
• 页数: 6页
• 语种: 英文
• DOI: 10.1088/1674-1056/aba274

摘要

Pseudospark-sourced electron beam is a promising candidate for driving vacuum electronic devices to generate mil-limeter wave and terahertz wave radiation as it has a very high combined beam current density. However, the inherent velocity spread of the beam, which is difficult to measure in experiment, has a great influence on the operating frequency and efficiency of the vacuum electronic device. In this paper, the velocity distribution characteristics of the electron beam produced by a single-gap hollow cathode electron gun are numerically studied and a three-dimensional kinetic plasma simulation model of a single-gap hollow cathode electron gun is built by using particle in cell and Monte Carlo collision methods in Vorpal. Based on the simulation model, the time-dependent evolution of the plasma formation inside the hollow cathode and electron beam generation process are observed. It is demonstrated that the pseudospark-sourced electron beam has a relatively large velocity spread. The time-dependent velocity distribution of the beam is analyzed, and the depen-dence of the beam velocity distribution under various operating conditions such as anode–cathode potential difference, gas pressure, and cathode aperture size are also studied.