1. Research Institute of Superconductor Electronics, School of Electronic Science and Engineering, Nanjing University, Nanjing 210023, China
2. Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
3. Department of Physics, University of Notre Dame, Notre Dame 46556, Indiana United States
4. Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, United States
5. Department of Physics, Northern Illinois University, DeKalb, Illinois 60115, United States
6. Purple Mountain Laboratories, Nanjing 211111, China