1. State Key Laboratory of Material Processing and Die and Mould Technology; School of Materials Science and Engineering; Huazhong University of Science and Technology (HUST); Wuhan 430074 P. R. China
2. High Magnetic Field Laboratory; Chinese Academy of Science; Hefei 230031 P. R. China
3. Department of Applied Physics; The Hong Kong Polytechnic University, Hung Hom; Kowloon Hong Kong 999077 P. R. China
4. Tianjin Key Laboratory of Molecular Optoelectronic Sciences; Department of Chemistry; Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300072 P. R. China