1. Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7) Department of Physics Princeton University Princeton NJ 08544 USA
2. Department of Physics National Cheng Kung University Tainan 70101 Taiwan
3. International Center for Quantum Materials School of Physics Peking University Beijing 100871 China
4. Max Planck Institute for Chemical Physics of Solids 01187 Dresden Germany
5. Department of Physics Princeton University Princeton NJ 08544 USA
6. Advanced Light Source E. O. Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
7. Princeton Institute for Science and Technology of Materials Princeton University Princeton NJ 08544 USA
8. Swiss Light Source Paul Scherrer Institute 5232 Villigen Switzerland
9. Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Singapore
10. Center for Quantum Frontiers of Research and Technology (QFort) Tainan 701 Taiwan
11. Physics Division National Center for Theoretical Sciences Taipei 10617 Taiwan
12. Lawrence Berkeley National Laboratory Berkeley CA 94720 USA