Affiliation: | CHEN Qinghu, FANG Minghu, YE Xisheng, JIAO Zhengkuan ZHANG Qirui, WEN Haihu and ZHAO Zhongxian! Physics Department, Zhejiang University, Hangzhou 310027, China;2. State Key Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China |