1. Department of Geological Sciences, Stanford University, Stanford, CA 94305, USA.
2. Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA.
3. Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, USA.
4. Center for High Pressure Science and Technology Advanced Research, Beijing 100094, China.
5. Center for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637, USA.