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. Ministry of General Education, Anhui Xinhua University, No. 555 Wangjiangxi Road, Hefei, Anhui Province 230026, PR China
3. New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China
4. Physics Experiment Teaching Center, School of Physical Sciences, University of Science and Technology of China, Hefei 230026, PR China