1. School of Physics
2. Beijing Institute of Technology
3. Beijing 100081
4. China
5. Laboratory of Theoretical and Computational Nanoscience
6. CAS Key Laboratory of Standardization and Measurement for Nanotechnology
7. CAS Center for Excellence in Nanoscience
8. National Center for Nanoscience and Technology
9. Chinese Academy of Sciences
10. Beijing 100190
11. CAS Key Laboratory for Nanosystem and Hierarchy Fabrication