1. Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031, China
2. University of Science and Technology of China, Hefei, Anhui 230026, China
3. Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
4. Advanced Energy Research Center, Shenzhen University, Shenzhen 518060, China
5. Center for Plasma Material Interactions, University of Illinois, Urbana-Champaign, Maryland 21211, USA
6. Johns Hopkins University, Baltimore, Maryland 21211, USA
7. CAS Key Laboratory of Photovoltaic and Energy Conservation Materials, Hefei 230031, China