1. Institute of Applied Physics and Materials Engineering, University of Macau, 999078 Macao SAR, P.R. China
2. Institute of Semiconductor Science and Technology, South China Normal University, Guangzhou 510631, P. R. China
3. Institute of Semiconductor Science and Technology, South China Normal University, Foshan 528225, P. R. China
4. College of Electrical Engineering, Hebei University of Architecture, Zhangjiakou 075000, P.R. China
5. Information Technology Research Institute, Shenzhen Institute of Information Technology, Shenzhen 518172, P.R. China
6. Guangdong Engineering Research Center of Optoelectronic Functional Materials and Devices, Guangzhou 510631, P.R. China