1 State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
2 Center of Materials Science and Opto-Electronic Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
3 State Key Laboratory of Integrated Optoelectronics, College of Electronic Science & Engineering, Jilin University, Changchun 130012, China
4 National Key Laboratory of Science and Technology on Electronic Test and Measurement, the 41st Research Institute, China Electronics Technology Group Corporation, Qingdao 266555, China