1. School of Physics, Hefei University of Technology, Hefei 230009, Anhui, China
2. State Key Laboratory of Quantum Optics and Quantum Optics Devices, Shanxi University, Taiyuan 030006, China
3. School of Materials Science and Engineering, Anhui University, Hefei 2300601, Anhui, China
4. Department of Materials Science & Engineering, City University of Hong Kong, Kowloon 999077, Hong Kong, China
5. Department of Chemistry, University of Nebraska─Lincoln, Lincoln, Nebraska 68588, United States