1. School of Materials Science and Engineering, Beihang University, Beijing 100191, China
2. Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100872, China
3. Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China
4. University of Science and Technology of China, Hefei, Anhui 230026, China
5. State Key Laboratory of Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
6. CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
7. University of Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing 100049, China
8. Department of Physics, Southern University of Science and Technology, Shenzhen 518005, China
9. State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Weijin Road, CN-300072 Tianjin, China
10. Department of Quantum and Energy Materials, International Iberian Nanotechnology Laboratory (INL), Avenida Mestre José Veiga s/n, Braga 4715-330, Portugal
11. National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
12. School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China