1. School of Physics and Astronomy, Beijing Normal University, Beijing 100875, P.R. China
2. Department of Physics, School of Physical Science and Technology, Xiamen University, Xiamen 361005, China
3. School of Physics, Zhejiang University, Hangzhou 310027, P. R. China
4. Center for Quantum Matter, Zhejiang University, Hangzhou 310027, P. R. China
5. Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing 100875, China