1. Department of Physics, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
2. Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
3. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
4. Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
5. College of Science, Nanjing University of Science and Technology, Nanjing 210094, China
6. Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, D-70569 Stuttgart, Germany
7. Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
8. School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
9. Department of Physics, National Taiwan University, Taipei 10617, Taiwan
10. Institute for Materials Science, University of Stuttgart, Germany