1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, People's Republic of China
2. Department of Mathematics and Physics, Anhui Jianzhu University, Hefei 230022, People's Republic of China
3. High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, People's Republic of China
4. Collaborative Innovation Centre of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China