1. College of Information Science and Engineering, Henan University of Technology, Zhengzhou 450001, Henan, PR China
2. Guangdong Provincial Key Laboratory of Information Photonics Technology, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, Guangdong, PR China
3. School of Semiconductor Science and Technology, South China Normal University, Foshan 528225, Guangdong, PR China
4. State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, PR China
5. College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, Guangdong, PR China
6. College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, PR China