Extreme-scale quantum simulations of materials reach 100 million atoms
Extreme-Scale Linear-Scaling Kohn-Sham DFT at 100 Million Atoms: Bridging Quantum Simulations and Experiments
Computational Engineering, Finance, and ScienceDistributed, Parallel, and Cluster Computing
Summary
Simulating materials at the level of individual atoms is usually very slow and limited to tiny pieces. The authors created a new method called XLSDFT that speeds up these simulations dramatically while keeping them accurate. They used this to simulate a silicon crystal with 200 million atoms and a complex battery interface with over 11 million atoms, much bigger than before. Their simulations matched real experiments, helping us understand how lithium interacts with battery materials at the atomic level.
What this means in practice
- •For materials simulation teams: Perform large-scale quantum simulations of solids and interfaces with up to hundreds of millions of atoms, bridging simulation size with experimental scales.
- •For battery development teams: Model atomic-level interactions in solid-state battery interfaces to better understand and optimize lithium metal reactions with electrolytes.
Authors
Qimen Xu, Yu Zhang, Dixing Ni, Lei Gao, Guangnan Feng, Qinrui Zheng, Jianting Liu, Haitian Lu, Zhaopeng Jia, Wei Xue, Shriram Chandran, Torsten Hoefler, Haohuan Fu, Yutong Lu
Abstract
Kohn-Sham density functional theory (DFT) remains the workhorse of ab initio materials simulation, yet cubic computational and quadratic memory scaling have confined calculations to a few hundred to thousands of atoms, spanning only nanometers, far below experimentally relevant length scales. We introduce XLSDFT, a linear-scaling DFT framework based on divide-and-conquer decomposition of the one-particle density matrix and Chebyshev-filtered subspace iteration, achieving linear computational and memory scaling while retaining DFT accuracy. Deployed on the LineShine exascale supercomputer, XLSDFT reduces computational complexity by orders of magnitude, enabling unprecedented DFT scale: a 200-million-atom silicon crystal, twentyfold beyond the prior record. Our implementation achieves 96.6% weak-scaling efficiency and sustained 157.9 Pflop/s (FP64) for a 100-million-atom scaling study. We further simulate an 11-million-atom all-solid-state battery interface of unprecedented complexity, 1,000 times beyond prior DFT for such systems, revealing how lithium metal reacts with the solid electrolyte at atomic resolution, in quantitative agreement with spectroscopy experiments.