1. Electronic Materials Research Laboratory, Key Laboratory of Ministry of Education & Shaanxi Engineering Research Center of Advanced Energy Materials and Devices, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, P. R. China
2. Institute of Special Environments Physical Sciences, Harbin Institute of Technology, Shenzhen 518055, P. R. China
3. Institute for Superconducting and Electronic Materials (ISEM), University of Wollongong, Innovation Campus, Squires Way, North Wollongong, NSW 2500, Australia