1. State Key Laboratory of Optoelectronic Materials and Technologies and School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275, People's Republic of China
2. SYSU-CMU Shunde International Joint Research Institute, Shunde 528399, Guangdong, People's Republic of China
3. School of Physics and Engineering, Henan University of Science and Technology, Luoyang 471023, People's Republic of China