Synthesis of the post-diamond BC8 phase of carbon with exascale computers and experiment

Uncovering the behavior of matter under extreme pressures and temperatures is crucial for understanding the interiors of exoplanets and harnessing ablator materials for inertial confinement fusion. Recent advancements in powerful laser compressions, in-situ X-ray diffraction, and exascale supercomputers have opened a new era of materials exploration with unprecedented detail.



In this talk, I will highlight transformative advances in predicting the synthesis pathways toward the elusive high-pressure BC8 post-diamond phase of carbon, revealed through quantum-accurate, billion-atom molecular dynamics shock simulations conducted on the DOE's exascale supercomputer, Frontier. By leveraging machine-learning interatomic potentials and the world’s most powerful computer, we simulate atomic-scale dynamics at experimental time (nanosecond) and length (micrometer) scales. These groundbreaking simulations are being validated through an experimental campaign at the National Ignition Facility.