1. Future Institute of Technology, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510515, P. R. China
2. Department of Applied Physics, The Hong Kong Polytechnic University, 999077 Hong Kong, P. R. China
3. The State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, School of Materials Science and Technology, South China University of Technology, Guangzhou, Guangdong 510640, P. R. China
4. Key Laboratory of Trauma & Tissue Repair of Tropical Area of PLA, Orthopedic Center, General Hospital of Southern Theater Command of PLA, Guangzhou 510010, Guangdong, P. R. China
5. Future Institute of Technology, South China Normal University, Guangzhou 510631, P. R. China