[SY-O7] Toward Exascale Atomistic Simulations of Interfaces
Invited
Under the U.S. Department of Energy, Aurora/A21 early science program, our group will be one of the 10 initial users of the Nation's first exaflop/s computer that can perform 1018 mathematical operations per second, when it is introduced in 2021. To make quantum molecular dynamics (QMD) and reactive molecular dynamics (RMD) simulations exa-scalable, we have developed an extension of the divide-and-conquer algorithmic framework called divide-conquer-recombine. On today's supercomputing platform, for instance, the framework has achieved over 98% of the perfect speedup on 786,432 IBM Blue Gene/Q processors for 40 trillion electronic degrees-of-freedom QMD in the framework of density functional theory and 68 billion-atom RMD. Production simulations include (1) 16,616-atom QMD simulation of rapid hydrogen production from water using metallic alloy nanoparticles, (2) 6,400-atom nonadiabatic QMD simulation of photoexcitation dynamics for efficient solar cells, and (3) 112 million-atom RMD simulation of metacarbon synthesis by high temperature oxidation of SiC nanoparticles. We will discuss tribology and interfacial applications such as frictional heating of energetic molecular crystals.