1National High Magnetic Field Laboratory, Tallahassee, FL 32310 USA
2College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 China
3Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
4Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
5Center for Condensed Matter Sciences, National Taiwan University, Taipei, 10617 Taiwan
6Institute of Physics, Academia Sinica, Taipei, 11529 Taiwan
7International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871 China
© The Author(s) 2017
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