1. Division of Nanomaterials and Nanochemistry, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P. R. China
2. Division of Theoretical and Computational Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P. R. China
3. Department of Modern Physics, University of Science & Technology of China, Hefei, Anhui, 230026, P. R. China