Towards Ab Initio Prediction of Superconducting Properties

非技术总结该奖项支持旨在开发和使用先进的计算方法在原子尺度上模拟超导材料的研究、计算和教育。超导，即电流在一定临界温度以下的无阻力流动，是量子力学在日常生活中最壮观的表现之一。这一特性正被开发在技术应用中，包括能量储存和分配、医药、电子和交通。在这个项目中，电子声子万尼尔(EPW)代码将实现新的功能，这是一个开源软件包，作为广泛使用的量子浓缩咖啡平台的组成部分分发。所开发的能力将使研究已知超导材料的趋势和通过使用高性能计算识别新的候选超导材料成为可能。这些方法将被应用于一类被称为过渡金属二卤化物的二维材料，以深入了解这些重要材料的超导机理，这些材料是最近基础和应用驱动研究的主题。该奖项支持计算材料科学和高性能计算方面的研究生和本科生的培训；这将有助于发展一支熟练的劳动力队伍，促进网络基础设施和计算材料研究的发展。为了帮助吸引新一代科学家进入STEM学科，PI的团队将参加为纽约州北部地区的小学生组织的外联活动。所有新的计算功能将免费提供给更广泛的物理学家、化学家和材料科学家社区。TECHNCIAL摘要该奖项支持研究、计算和教育，目的是应用理论/计算方法来模拟超导体，而不需要求助于可调参数。在拟议的项目中，将在开源EPW代码中引入新的高级功能，以实现对材料超导性质的预测计算。所开发的方法将通过计算块体和二维过渡金属二卤化物的超导性质来验证，二卤化物是一类包含电荷密度波、超导和拓扑非平凡相的化合物。PI将对研究生和本科生进行材料建模和编程方面的培训，并共同组织研讨会，教授EPW代码的基本理论和最佳使用。最后，为了提高中学生对科学的兴趣，PI的小组将作为宾厄姆顿大学物理推广计划组织的科学节目的一部分进行演示。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NONTECHNICAL SUMMARYThis award supports research, computation, and education aimed to develop and employ advanced computational methods for modeling superconducting materials at the atomic scale. Superconductivity, the resistance-free flow of electrical current below a certain critical temperature, is one of the most spectacular manifestations of quantum mechanics on the scale of everyday life. This property is being exploited in technological applications, including energy storage and distribution, medicine, electronics, and transportation.Within this project, new functionalities will be implemented in the electron-phonon Wannier (EPW) code, which is an open-source software package distributed as an integral part of the widely used Quantum ESPRESSO platform. The developed capabilities will enable the investigation of trends in known superconducting materials and the identification of new candidate superconducting materials through the use of high-performance computing. The methods will be applied to a class of two-dimensional materials called transition metal dichalcogenides to provide insights into the mechanism of superconductivity in these important materials which have been the subject of recent fundamental and application-driven research.This award supports training of graduate and undergraduate students in computational materials science and high-performance computing; this will contribute to the development of a skilled workforce for advancing cyberinfrastructure and computational materials research. To help attract a new generation of scientists into the STEM disciplines, the PI’s team will take part in outreach activities organized for elementary school students in the upstate New York area. All new computational features will be made freely available to reach a wider community of physicists, chemists, and materials scientists.TECHNCIAL SUMMARY This award supports research, computation, and education with the aim to apply theoretical/computational methods for modeling superconductors without resorting to adjustable parameters. Achieving quantitative agreement with experiment in present-day theoretical studies of superconducting properties is notoriously difficult because of electron-electron interactions, spin fluctuations, plasmonic effects, electron-phonon vertex corrections, and other factors that are commonly neglected or inadequately included. Within the proposed project, new advanced functionalities will be introduced into the open-source EPW code to enable predictive calculations of superconducting properties of materials. The developed methodology will be validated by performing calculations of the superconducting properties of bulk and two-dimensional transition metal dichalcogenides, a family of compounds that hosts charge density wave, superconducting, and topologically non-trivial phases. An important unresolved question in TMDs is why the calculated critical temperature and zero-temperature superconducting gap tend to be systematically overestimated compared to the experimental values.The developed tools will be released under the open-source GNU GPL to reach a wider community of scientists. The PI will train graduate and undergraduate students in materials modeling and programming, and co-organize workshops to teach the underlying theory and optimal usage of the EPW code. Finally, in order to raise middle school students' interest in science, the PI’s group will give demonstrations as part of the Science Shows organized by the Binghamton University’s Physics Outreach Program.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.