1. State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
2. Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai 200433, China
3. Laboratory for Computational Physical Sciences (MOE), Fudan University, Shanghai 200433, China
4. Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
5. School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China
6. Department of Physics, University of Washington, Seattle, WA 98195-1560, USA
7. Department of Electronic Engineering, Royal Holloway University of London, Egham TW20 0EX, UK
8. Materials Engineering, The University of Queensland, Brisbane QLD 4072, Australia
9. Beijing Key Lab of Microstructure and Property of Advanced Material, Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124, China
10. The Ultramicroscopy Research Center, Kyushu University, Fukuoka 819-0395, Japan
11. State Key Laboratory of ASIC and System, School of Microelectronics, Fudan University, Shanghai 200433, China
12. Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
13. Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, Fukuoka 819-0395, Japan
14. Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane QLD 4072, Australia
15. Shanghai Research Center for Quantum Sciences, Shanghai 201315, China