论文标题
开发碎片动力学蒙特卡洛方法，用于有效预测钙钛矿晶体的离子扩散
Development of a fragment kinetic Monte Carlo method for efficient prediction of ionic diffusion in perovskite crystals
论文作者
论文摘要
提出了一种大规模平行的动力学蒙特卡洛（KMC）方法，用于通过引入原子片段化方案（片段KMC）来模拟晶体系统中的离子迁移。片段KMC方法通过1728中央加工单元（CPU）核达到了合理的并行效率，该方法可以模拟离子扩散$ $ $ $ M级的钙钛矿晶体。为了证明所提出的方法的可行性，应用了片段KMC方法来预测srtio $ _ {（3-x）} $ h $ _x $和batio $ _ {（3-x）} $ h $ _x $ _x $ _x $ _X $ _X $ _X $ _x $ _X $ _X $ systems srtio $ _ {（3-x）} $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _x $ _X $ _x $ _x $ _x $ _x $ _x $ _X $ _X $ system。最后，在应用偏置电压下定制了针对$ $ $ $ scale batio $ _3 $模拟的片段KMC方法，并评估了Batio $ _3 $模型中的氧扩散。各自的晶粒尺寸为子纳米尺，我们得出结论，可以使用所提出的片段KMC方法来计算具有合理计算成本的完全原子模拟模型中$ $ $ scale材料中的离子迁移程度。
A massively parallel kinetic Monte Carlo (kMC) approach is proposed for simulating ionic migration in a crystal system by introducing the atomic fragmentation scheme (fragment kMC). The fragment kMC method achieved a reasonable parallel efficiency with 1728 central processing unit (CPU) cores, and the method enables the simulation of ionic diffusion in $μ$m-scale perovskite crystals. To demonstrate the feasibility of the proposed approach, the fragment kMC method was applied to predict the diffusion coefficients of hydrogen and oxygen in SrTiO$_{(3-x)}$H$_x$ and BaTiO$_{(3-x)}$H$_x$ system. Finally, the fragment kMC method was customized for $μ$-scale BaTiO$_3$ simulation under an applied bias voltage, and oxygen diffusion in BaTiO$_3$ model was evaluated. The respective grain sizes are sub-nanometre, and we conclude that the proposed fragment kMC method can be applied to calculate the extent of ionic migration in $μ$-scale materials with fully atomistic simulation models at a reasonable computational cost.
