Recent progress in research on micro-cathode arc thrusters Tianyuan Ji, Liqiu Wei, Fan Wu, Wenjia Jiang, Wenbo Li, Yongjie Ding, Hong Li, Jinyue Geng and Daren Yu Eur. Phys. J. D, 74 5 (2020) 83 Published online: 01 May 2020 DOI: 10.1140/epjd/e2020-10032-9