1. Tianjin Key Laboratory of Electronic Materials and Devices; School of Electronics & Information Engineering; Hebei University of Technology; 5340 Xiping Road, Beichen District Tianjin 300401 China
2. Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems; School of Materials Science & Engineering; Beijing Institute of Technology; 5 Zhongguancun South Street Haidian District, Beijing 100081 China
3. Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP); City University of Hong Kong; 83 Tat Chee Avenue Kowloon Hong Kong SAR China