Collaborative Research: NSCI: SI2-SSE: Time Stepping and Exchange-Correlation Modules for Massively Parallel Real-Time Time-Dependent DFT

合作研究：NSCI：SI2-SSE：大规模并行实时瞬态 DFT 的时间步进和交换相关模块

• 批准号: 1740204
• 负责人: Yosuke Kanai
• 金额: $ 25万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1740204&HistoricalAwards=false
• 关键词: Collaborative; Research; NSCI; SI2; SSE

Recent advances in high-performance (HPC) computing allow simulations of quantum dynamics of electrons in complex materials, and such simulations are central to advancing various medical and semiconductor technologies, ranging from proton beam cancer therapy to fabricating faster and smaller electronics. At the same time, the increasing scale and complexity of modern high-performance computers exposed a need for development of scientific software that is tailored for computers with large numbers of processors so that simulations can efficiently take advantage of increasing computing power. This project advances scientific software for simulating quantum dynamics of electrons for high-performance computers with tens and hundreds of thousands of processors that are becoming widely available. This work builds the HPC academic research community around the proposed software by extending the existing software available for quantum dynamics simulation with better user-friendly features and analysis techniques. In the process, this project engages graduate students and early-career researchers to use and further develop scientific software for high-performance computers in general. Additionally, a summer school for hands-on training will be conducted. The open source software will be made available to the community on Github (public repository). Real-time propagation in time-dependent density functional theory (RT-TDDFT) is becoming increasingly popular for studying non-equilibrium electronic dynamics both in the linear regime and beyond linear response. RT-TDDFT can be combined to study coupled dynamics of quantum-mechanical electrons with the movement of classical ions within Ehrenfest dynamics. In spite of its great promise, RT-TDDFT is computationally very demanding, especially for studying large condensed-matter systems. The large cost arises from small time steps of numerical integration of the electron dynamics, rendering accurate (hybrid) exchange-correlation (XC) functionals unfeasible, despite their clear benefits. In addition, while modern high-performance computing (HPC) helps tackling great scientific questions, massively parallel, hybrid-paradigm architectures present new challenges. Theoretical and algorithmic methods need to be developed in order to take full advantage of modern massively parallel HPC. This work builds new modules for the RT-TDDFT software component of the Qb@ll code, that enables a large community of researchers to perform advanced first-principles simulations of non-equilibrium electron dynamics in complex condensed-phase systems, using massively parallel HPC. This is done through developing (1) new modules for numerical integration that propagate the underlying non-linear partial differential equations in real time with high efficiency and accuracy, and (2) new modules for improved approximations of the underlying electronic structure, using a modern meta-generalized-gradient XC functional. Furthermore, the work builds the HPC academic research community around RT-TDDFT within the Qb@ll code through (1) development of user-friendly features that interface Qb@ll with other code and analysis techniques and (2) engagement of early-career scientists by incorporating hands-on training on RT-TDDFT using the Qb@ll code in TDDFT summer school.This project is supported by the Office of Advanced Cyberinfrastructure in the Directorate for Computer and Information Science and Engineering, the Materials Research Division and Chemistry Division in the Directorate of Mathematical and Physical Sciences.

高性能（HPC）计算的最新进展允许模拟复杂材料中电子的量子动力学，并且此类模拟对于推进各种医疗和半导体技术的核心，从质子束癌症治疗到制造更快，较小的电子设备。同时，现代高性能计算机的规模和复杂性的日益扩展和复杂性暴露了开发科学软件的需求，该软件是针对具有大量处理器的计算机量身定制的，因此模拟可以有效利用增加计算能力的优势。该项目推进了科学软件，用于模拟具有数十万种处理器的高性能计算机的电子动力学，这些计算机已广泛可用。这项工作通过扩展可用于用户友好型功能和分析技术的量子动力学模拟的现有软件来建立HPC学术研究界。在此过程中，该项目与研究生和早期研究人员一起使用并进一步开发一般的高性能计算机科学软件。此外，还将进行一所暑期培训。开源软件将在GitHub（公共存储库）上提供给社区。时间依赖性密度功能理论（RT-TDDFT）的实时传播在研究线性态度和超越线性响应中的非平衡电子动力学方面变得越来越流行。可以将RT-TDDFT合并，以研究量子力学电子的耦合动力学，并在Ehrenfest动力学中的经典离子运动。尽管有巨大的希望，RT-TDDFT在计算上非常苛刻，尤其是用于研究大型凝结系统的系统。较高的成本来自电子动力学数值集成的小时步，尽管具有明显的好处，但仍使准确的（混合）交换相关（XC）功能不可行。此外，尽管现代高性能计算（HPC）有助于解决巨大的科学问题，但大规模平行的混合范式体系结构带来了新的挑战。为了充分利用现代平行的HPC，需要开发理论和算法方法。这项工作为QB@ll代码的RT-TDDFT软件组件构建了新模块，这使大量的研究人员能够使用大量并行HPC对复杂的冷凝阶段系统中的非平衡电子动力学进行高级第一原理模拟。这是通过开发（1）用于数值集成的新模块来实现的，该模块以高效率和准确性实时实时传播非线性偏微分方程，以及（2）使用现代化的元元化元素梯度XC XC功能的新模块，以改善基础电子结构的近似值。此外，这项工作还通过（1）开发QB@ll代码中的RT-TDDFT围绕RT-TDDFT建立了HPC学术研究界计算机和信息科学与工程局的网络基础设施，材料研究部和化学部数学和物理科学局。

项目成果

First-Principles Modeling of Electronic Stopping in Complex Matter under Ion Irradiation

离子辐照下复杂物质电子停止的第一性原理建模

• DOI: 10.1021/acs.jpclett.9b02975
• 发表时间: 2019
• 期刊: The Journal of Physical Chemistry Letters
• 作者: Yost, Dillon C.;Yao, Yi;Kanai, Yosuke
• 通讯作者: Kanai, Yosuke

Dynamical transition orbitals: A particle–hole description in real-time TDDFT dynamics

动态跃迁轨道：实时 TDDFT 动力学中的粒子空穴描述

• DOI: 10.1063/5.0035435
• 发表时间: 2021
• 期刊: The Journal of Chemical Physics
• 作者: Zhou, Ruiyi;Kanai, Yosuke
• 通讯作者: Kanai, Yosuke