1. State
Key Laboratory of Superhard Materials, College of Materials Science
and Engineering, Jilin University, 2699 Qianjin Street, Changchun, Jilin 130012, China
2. College
of Physics, Jilin University, Changchun, Jilin 130012, China
3. Geophysical
Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, DC 20015, United States
4. Institute
of Condensed Matter Physics, Linyi University, Linyi 276005, China