1. Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, P. R. China
2. University of Chinese Academy of Sciences, Beijing 100049, P. R. China
3. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, P. R. China
4. Center for High Pressure Science & Technology Advanced Research, Shanghai 201203, P. R. China