1. Department of Physics and Optoelectronic Engineering, Faculty of Science, Beijing University of Technology, Beijing100124, China
2. State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing100083, China
3. Songshan Lake Materials Laboratory, Dongguan523808, China
4. National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu610054, China