1. Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, School of Physical Sciences, University of Science and Technology of China, Hefei 230026, PR China
2. CAS Key Laboratory of Microscale Magnetic Resonance, and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
3. Physics Experiment Teaching Center, School of Physical Sciences, University of Science and Technology of China, Hefei 230026, PR China