| Affiliation: | National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093; Structural Research Laboratory, University of Science and Technology of China, Hefei, A nhui 230026; and Department of Physics, Yunnan Normal University,Kunming 650092 National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing,210093 National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing,210093 |
