1. Department of Physics, Wuhan University of Technology, Wuhan 430070, China
2. School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
3. Centre for Mathematical Plasma-Astrophysics, Department of Mathematics, University of Leuven, Leuven 3001,
Belgium
4. School of Physics Science and Technology, Anshan Normal University, Anshan 114007, China