1. Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072, China
2. Institute of Semiconductors, Henan Academy of Sciences, Zhengzhou 450000, China
3. Wuhan Institute of Quantum Technology, Wuhan 430206, China
4. Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100190, China