1. Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, Xi’an Jiaotong University, Xi’an 710049, People’s Republic of China
2. Department of Physics
and Astronomy, University of Texas at San Antonio, Texas 78249, United States
3. Department of Materials
Science and Engineering, University of Texas at Arlington, Arlington, Texas 76019, United States
4. Department of Mechanical
Engineering, University of Houston, Houston, Texas 77204, United States
5. The Texas Center for
Superconductivity and Department of Chemistry, University of Houston, Houston, Texas 77204, United
States
6. Department
of Chemistry, North Carolina State University, Raleigh,
North Carolina 27695-8204, United States