1 Electronic Materials Research Laboratory (Key Laboratory of Ministry of Education), State Key Laboratory for Mechanical Behavior of Materials and School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
2 Institute of Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong, Wollongong 2522, Australia.
3 Electronic Materials Research Laboratory (Key Laboratory of Ministry of Education), State Key Laboratory for Mechanical Behavior of Materials and School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China. Electronic address: ful5@xjtu.edu.cn.