1. Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, People’s Republic of China
2. School of Materials Science and Engineering, Beihang University, Beijing 100191, People’s Republic of China
3. Collaborative Innovation Center of Quantum Matter, Beijing 100084, People’s Republic of China
4. Institute for Advanced Study, Tsinghua University, Beijing 100084, People’s Republic of China