SI2-SSE: Expanding the Scope of Materials Modeling with Electron Phonon Wannier (EPW) Software

引入有效的非经验计算方法来模拟和预测先进材料的性质，是加速理论指导的材料发现的持续努力的核心。开源软件Electron-Phonon-Wannier(EPW)代码提供了在量子力学水平上进行高精度性质计算的独特能力。特别是，EPW提供了对支配电子和原子振动之间相互作用的微观机制的洞察。在这个项目中，现有的能力将扩展到对具有复杂电子和磁性的更广泛的材料进行建模。这些知识可以用来设计新一代材料，用于收集太阳能和热能，从电子学过渡到自旋电子学，或者实现物质的奇异状态。EPW将为广泛的电子结构社区提供服务，这些社区包括物理学家、材料科学家、化学家和工程师，他们致力于热电、光伏、超导、自旋电子和其他应用的下一代材料的建模和设计。高性能材料的开发对于应对与能源和环境、交通以及信息和通信技术有关的紧急社会挑战至关重要。开发的计算工具将根据GNU通用公共许可证发布，以确保科学界将直接和及时地受益于这项技术。该项目范围广泛的教育和外联活动将促进和普及不同社区的科学研究。计划在美国和欧洲举办的EPW实践研讨会将有助于创建一个强大的EPW社区，以进一步开发该守则，并促进来自不同国家的参与者之间的新的研究合作。为纽约州北部地区的小学生举办的互动活动将有助于吸引新一代科学家从代表不足的群体进入STEM学科。电子结构社区目前的重点是引入新的能力，使设计用于热电、光伏、超导、自旋电子和其他应用的新兴高性能材料成为可能。众所周知，使用目前基于密度泛函理论的方法很难以期望的精度评估这些应用中的函数定义属性。这个项目的目的是扩展开源软件Electron-Phonon-Wannier(EPW)的功能，扩大其在材料研究领域的影响。EPW现在作为Quantum Epresso套件的一部分分发，已成为一种独特的计算工具，提供标准电子结构封装中无法提供的功能。通过结合密度泛函微扰理论和极大局域Wannier函数方法，EPW使计算数百万个电子-声子矩阵元成为可能。这项拟议的工作将扩展EPW代码的现有功能，以模拟一类重要的自旋相关材料属性。建议的方法论和面向用户的目标是与SSE计划和DMR的重点方向保持一致，这些方向与创建、扩展和部署面向大量用户的健壮软件有关。特别是，对自旋输运、自旋驰豫和自旋动力学的预测计算可以在原子尺度上提供对过程的基本见解，并为合理设计新材料和指导实验工作提供必要的基础。该项目还将在大型计算基础设施上提供日常科学实验的轻松管理和执行。用于自动化、存储、管理和共享模拟的工作流的引入将促进数据透明度和通信，并将数据驱动的材料设计推进到新的前沿。这些目标的成功实施将大大增强EPW规则的功能，并确保EPW用户社区的持续增长。开发的计算工具将根据GNU通用公共许可证发布，以确保科学界将直接和及时地受益于这项技术。研究计划将与教育和外展活动紧密结合。它将使学生能够在先进的电子结构方法、计算材料科学和高性能计算方面进行跨学科培训。其他努力将包括向小学生进行科学演示，开发一门材料建模的特殊课程，将计算机模拟纳入宾厄姆顿大学的本科和研究生课程，以及组织研讨会，教授基本理论和EPW代码的优化使用。该项目得到了计算机与信息科学和工程局的高级网络基础设施办公室和数学和物理科学局的材料研究部的支持。

Introduction of efficient non-empirical computational methods for modeling and predicting advanced materials properties is at the heart of the on-going effort to accelerate theory-guided materials discovery. The open-source software Electron-Phonon-Wannier (EPW) code offers unique capabilities for high-accuracy calculations of properties at the quantum mechanical level. In particular, EPW provides insight into the microscopic mechanisms that govern the interaction between electrons and atomic vibrations. Within this project, the existing capabilities will be extended to model a wider range of materials with complex electronic and magnetic properties. The knowledge can be used to design new-generation materials for harvesting of solar and thermal energy, making transition from electronics to spintronics, or realizing exotic states of matter. EPW will serve the broad electronic structure community of physicists, materials scientists, chemists, and engineers who work on modeling and designing next-generation materials for thermoelectric, photovoltaic, superconducting, spintronic, and other applications. The development of high-performance materials is crucial for addressing emergent societal challenges related to energy and environment, transportation, and information and communication technologies. The developed computational tools will be released under the GNU General Public License to ensure that the scientific community will directly and timely benefit from this technology. A broad spectrum of educational and outreach activities proposed within the project will promote and popularize scientific research in diverse communities. Planned hands-on workshops on EPW in the US and Europe will help create a strong EPW community for further development of the code and foster new research collaborations among participants from different countries. Interactive events for elementary school students in the upstate New York area will help attract a new generation of scientists from underrepresented groups into the STEM disciplines.The current focus of the electronic structure community is to introduce new capabilities enabling the design of emerging high-performance materials for thermoelectric, photovoltaic, superconducting, spintronic, and other applications. Function-defining properties in these applications are notoriously difficult to evaluate with desired accuracy using present density functional theory-based methods. The aim of this project is to expand the functionalities and broaden the impact of the open-source software Electron-Phonon-Wannier (EPW) in the area of materials research. EPW, now distributed as part of the Quantum ESPRESSO suite, has emerged as a unique computational tool that offers functionalities not available in standard electronic structure packages. By combining density-functional perturbation theory and maximally-localized Wannier functions methods, EPW makes it computationally feasible to calculate millions of electron-phonon matrix elements. The proposed work will expand the current capabilities of the EPW code to modeling an important class of spin-dependent materials properties. The proposed methodological, and user-oriented objectives are chosen to align with the focal directions of the SSE program and the DMR pertaining to creation, expansion, and deployment of robust software targeting a large user base. In particular, predictive calculations of spin transport, spin relaxation, and spin dynamics can yield fundamental insights into processes at the atomic scale and provide the necessary foundation to rationally design new materials and guide experimental work. The project will also provide easy management and execution of day to day scientific experiments on large-scale computing infrastructures. The introduction of workflows for automating, storing, managing, and sharing simulations will facilitate data transparency and communication as well as advance data-driven materials design to new frontiers. Successful implementation of these objectives will substantially enhance the functionalities of the EPW code and ensure the continued growth of the EPW user community. The developed computational tools will be released under the GNU General Public License to ensure that the scientific community will directly and timely benefit from this technology. The research program will be tightly integrated with educational and outreach activities. It will enable interdisciplinary training of students in advanced electronic structure methods, computational material science, and high-performance computing. Other efforts will include science demonstrations to elementary school students, development of a special course in materials modeling to incorporate computer simulations in the Binghamton University's undergraduate and graduate curriculum, and organization of workshops to teach the underlying theory and optimal usage of the EPW code.This project is supported by the Office of Advanced Cyberinfrastructure in the Directorate for Computer & Information Science and Engineering and the Division of Materials Research in the Directorate of Mathematical and Physical Sciences.