1. CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei 230026, China
2. Mengcheng National Geophysical Observatory, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
3. Hefei National Laboratory for the Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China