1. Center for High Pressure Science and Technology Advanced Research; Beijing 100094 P.R. China
2. Geophysical Laboratory; Carnegie Institution of Washington; Washington DC 20015 USA
3. Neutron Sciences Directorate; Oak Ridge National Laboratory; Oak Ridge TN 37830 USA
4. Institute of Physics; Chinese Academy of Sciences; Beijing 100190 China
5. Collaborative Innovation Center of Quantum Matter; Beijing China
6. HPSynC, Geophysical Laboratory; Carnegie Institution of Washington; Argonne IL 60439 USA