作者机构:[1]lnstitute for Advanced Study, Tsinghua University, Beijing 100084, China, [2]Department of Physics, Peking University, Beijing 100871, China, [3]Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, [4]Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
相关基金:This work was supported by the National Key Research and Development Plan (2016YFA0301600), the National Natural Science Foundation of China (11325418) and Tsinghua University Initiative Scientific Research Program. We would like to thank Yingfei Gu, Chaoming Jian, Xiaoliang Qi and Xi Dong for helpful discussions.