1. State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences 1 , Beijing 100083, China
2. Center of Materials Science and Optoelectronic Engineering, University of Chinese Academy of Sciences 2 , Beijing 100049, China
3. School of Materials Science and Engineering, University of Science and Technology Beijing 3 , Beijing 100083, China
4. Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences 4 , Beijing 100049, China