Affiliation: | 1. Superconductivity Research Group, School of Materials Science and Engineering, University of New South Wales, Sydney, 2052 NSW,, Australia 2. Key Laboratory for Levitation Technology and Maglev Trains, Ministry of Education of China, Superconductivity and NewEnergy Center (SNEC), Southwest Jiaotong University, Chengdu 610031, China 3. Department of Physics, Peking University, Beijing 100871, China |