Affiliation: | Northwest Institute for Nonferrous Metal Research, P.O. Box 51, Xi’an 710016, China; Kyushu Institute of Technology, 680-4 Kawazu, Iizuka Fukuoka 820-8502, Japan; Superconducting Materials Research Group, Korea Electrotechnology Research Institute, Bulmosangil 70, Changwon 641-120, Republic of Korea; Cryogenic Lab, Inter University Accelerator Centre (IUAC), Aruna Asaf Ali Marg, New Delhi 110067, India |