1. State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, No. A35, Qinghua East Road, Haidian District, Beijing 100083, China
2. Center of Materials Science and Optoelectronic Engineering, University of Chinese Academy of Sciences, No. 19A, Yuquan Road, Shijingshan
District, Beijing 100049, China