1. Siyuan Laboratory, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy Materials, Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Department of Physics, Jinan University, Guangzhou, Guangdong 510632, P. R. China
2. Instrumental Analysis & Research Center, Sun Yat-sen University, Guangzhou, Guangdong 510275, P. R. China