1. Department of Physics, The Chinese University of Hong Kong, New Territories 999077, Hong Kong SAR, China
2. Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute & Chinese Academy of Sciences, Shanghai 201204, China
3. Department of Applied Physics, Research Institute for Smart Energy, The Hong Kong Polytechnic University, Kowloon 999077, Hong Kong SAR, China
4. Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong SAR, China
5. National Synchrotron Radiation Research Center, Hsinchu Science Park, Hsinchu 30076, Taiwan