1. Anhui Key Laboratory for Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
2. University of Science and Technology of China, Hefei 230026, China
3. Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100080, China
4. School
of Material Science and Engineering, Shanghai University, Shanghai 200072, China