1. Institute of Atomic and Molecular Physics Sichuan University Chengdu Sichuan 610065 P. R. China
2. Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 P. R. China
3. School of Physical Science and Technology ShanghaiTech University Shanghai 201210 P. R. China
4. University of Chinese Academy of Sciences Beijing 100049 P. R. China
5. Metrology Research Centre National Research Council Canada Ottawa Ontario K1A 0R6 Canada
6. Analytical & Testing Center Sichuan University Chengdu Sichuan 610065 P. R. China
7. Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204 P. R. China
8. Engineering Research Center in Biomaterials Sichuan University Chengdu Sichuan 610065 P. R. China