1. Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
2. School of Physics, Harbin Institute of Technology, Harbin 150081, China
3. Materials Characterization and Preparation Center, Southern University of Science and Technology, Shenzhen 518055, China
4. Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
5. School of Materials Science and Engineering, Dongguan University of Technology, Dongguan 523808, China