1. University of California, Irvine, California 92697, USA
2. Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
3. University of Chinese Academy of Sciences, Beijing 100049, China
4. TAE Technologies, Inc., 19631 Pauling, Foothill Ranch, California 92610, USA
5. Fusion Simulation Center, Peking University, Beijing 100871, China