CDS&E: Computational Studies of Weyl Semimetals: Disorder, Correlations and Topological Properties

CDS

基本信息

批准号：
1832728
负责人：
Sergey Savrasov
金额：
$ 35.85万
依托单位：
University of California-Davis
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-01 至 2022-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1832728&HistoricalAwards=false
关键词：
CDS&amp Computational Studies Weyl Semimetals

项目摘要

NONTECHNICAL SUMMARYThis award supports computational and theoretical research and education towards discovering and studying the properties of new Weyl semimetals. These are new types of materials that have been recently proposed theoretically and are now beginning to be discovered. They are very poor conductors in their bulk but have highly conductive metallic surfaces. These materials are special in that their surface enjoys what is called topological protection, meaning that it cannot be changed without destroying the bulk material. In most materials, surfaces can be chemically altered as they tend to pick up impurities from the environment, which in turn interfere with how materials conduct electricity, a crucial feature for applications in any electronic device. However, the topologically protected surfaces of Weyl semimetals are robust to impurities. This research project aims to develop methods for finding new Weyl semimetals, and for understanding their properties using computer-based simulations. The close competition between various degrees of freedom of the electrons in these materials makes their study particularly challenging, but also holds great promise for new functionalities.The research will lead to new methods, algorithms, and software that will enhance and simplify our ability to carry out material-specific studies and to promote the gradual improvement of materials by computer-aided design, thus shortening currently expensive and inefficient trial-and-error procedures. Developing scientific software tools that incorporate computer programs into a user-friendly interface lowers the barrier to entry for the computational exploration of the properties of quantum materials. The development of these user-friendly interfaces will also facilitate the teaching of elementary theories of topological materials at advanced undergraduate and graduate levels, thereby enhancing University curricula.TECHNICAL SUMMARYThis award supports the development of computational approaches that are based on density-functional theory combined with dynamical-mean-field and perturbation theories, which will allow finding new topological semimetals and studying their single-particle spectra, transport, magnetic, and superconducting properties. Guided by similarities between crystal structures and topological features of known systems, realizations of the band inversion mechanism between electronic states of different parity, hybridization effects between partially filled strongly correlated states with filled or empty topological energy bands, chemical valence arguments and physical intuition, a high-throughput screening of materials for their topological properties will be performed in the infinite space of chemically allowed compounds using computer-based simulations.These findings will allow identifying new topological materials, such as Weyl semimetals, and, in particular, those with only Weyl nodes and no other Fermi surface states. Such discoveries could motivate further experimental studies of the chiral anomaly and topological superconductivity. Theoretical and computational approaches to predict and study complex behavior in these systems would potentially influence the design of quantum materials with unique characteristics that rely on topological protection of states, which are at the frontier of materials science.The research will lead to new methods, algorithms, and software that will enhance and simplify our ability to carry out material-specific studies and to promote the gradual improvement of materials by computer-aided design, thus shortening currently expensive and inefficient trial-and-error procedures. Developing scientific software tools that incorporate computer programs into a user-friendly interface lowers the barrier to entry for the computational exploration of the properties of quantum materials. The development of these user-friendly interfaces will also facilitate the teaching of elementary theories of topological materials at advanced undergraduate and graduate levels, thereby enhancing University curricula.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.

非技术摘要这一奖项支持计算和理论研究和教育，以发现和研究新的Weyl半学的特性。这些是最近在理论上提出的新型材料，现在开始被发现。它们的批量是非常差的导体，但具有高导电的金属表面。这些材料是特殊的，因为它们的表面享有所谓的拓扑保护，这意味着如果不破坏散装材料，它就无法更改。在大多数材料中，表面可以化学改变，因为它们倾向于从环境中拾取杂质，从而干扰了材料如何传导电力，这是任何电子设备中应用的关键特征。但是，Weyl半法的拓扑保护表面对杂质是可靠的。该研究项目旨在开发寻找新的Weyl半学的方法，并使用基于计算机的模拟来理解其属性。这些材料中各种电子自由度之间的近距离竞争使他们的研究特别具有挑战性，但对新功能有很大的希望。该研究将导致新方法，算法和软件，以增强和简化我们的携带能力消除特定于材料的研究，并通过计算机辅助设计逐步改善材料，从而缩短当前昂贵且效率低下的试用程序。开发将计算机程序纳入用户友好的界面中的科学软件工具降低了进入量子材料属性的计算探索的障碍。这些用户友好的接口的开发还将促进高级本科和研究生级别的拓扑材料基本理论的教学，从而增强了大学课程。技术摘要颁发奖项支持基于密度官能理论的计算方法的发展动态均值场和扰动理论将允许找到新的拓扑半学并研究其单粒子光谱，传输，磁性和超导性特性。在晶体结构与已知系统的拓扑特征之间的相似性的指导下，频带反演机制不同奇偶校验的电子状态之间的实现，通过填充或空的拓扑能量带，化学价参数和物理直觉，部分相关状态之间的杂交效应，杂交效应，一种使用基于计算机的模拟，将在化学允许的化合物的无限空间中对其拓扑特性的材料进行高通量筛选。这些发现将允许识别新的拓扑材料，例如Weyl Semimetals，尤其是那些只有Weyl的材料节点和其他费米表面状态。这些发现可以激发手性异常和拓扑超导性的进一步实验研究。在这些系统中预测和研究复杂行为的理论和计算方法可能会影响具有依赖状态拓扑保护的量子材料的设计，这些量子在材料科学的边界。以及将增强和简化我们进行特定于材料的研究并通过计算机辅助设计逐步改进材料的软件，从而缩短当前昂贵且效率低下的试用程序。开发将计算机程序纳入用户友好的界面中的科学软件工具降低了进入量子材料属性的计算探索的障碍。这些用户友好型界面的开发还将促进高级本科和研究生级别的拓扑材料基本理论的教学，从而增强了大学课程。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子来支持的。优点和更广泛的影响审查标准。

项目成果

期刊论文数量（8）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Renormalized quasiparticles, topological monopoles, and superconducting line nodes in heavy-fermion CeTX3 compounds

DOI：
10.1103/physrevb.103.l041112
发表时间：
2020-05
期刊：
arXiv: Strongly Correlated Electrons
影响因子：
0
作者：
V. Ivanov;X. Wan;S. Savrasov
通讯作者：
V. Ivanov;X. Wan;S. Savrasov

Lifshitz transition and frustration of magnetic moments in infinite-layer NdNiO2 upon hole doping

DOI：
10.1103/physrevb.101.241108
发表时间：
2020-03
期刊：
Physical Review B
影响因子：
3.7
作者：
I. Leonov;I. Leonov;S. Skornyakov;S. Skornyakov;S. Savrasov
通讯作者：
I. Leonov;I. Leonov;S. Skornyakov;S. Skornyakov;S. Savrasov

Millimetre-long transport of photogenerated carriers in topological insulators

DOI：
10.1038/s41467-019-13711-3
发表时间：
2019-12
期刊：
Nature Communications
影响因子：
16.6
作者：
Yasen Hou;Rui Wang;Ruijuan Xiao;L. McClintock;Henry Clark Travaglini;John Paulus Francia;H. Fetsch;O. Erten;S. Savrasov;Baigeng Wang;A. Rossi;I. Vishik;E. Rotenberg;Dong Yu
通讯作者：
Yasen Hou;Rui Wang;Ruijuan Xiao;L. McClintock;Henry Clark Travaglini;John Paulus Francia;H. Fetsch;O. Erten;S. Savrasov;Baigeng Wang;A. Rossi;I. Vishik;E. Rotenberg;Dong Yu

Two phase transitions driven by surface electron doping in WTe2

DOI：
10.1103/physrevb.102.121110
发表时间：
2020-09
期刊：
Physical Review B
影响因子：
3.7
作者：
A. Rossi;G. Resta;S. Lee;R. Redwing;C. Jozwiak;A. Bostwick;E. Rotenberg;S. Savrasov;I. Vishik
通讯作者：
A. Rossi;G. Resta;S. Lee;R. Redwing;C. Jozwiak;A. Bostwick;E. Rotenberg;S. Savrasov;I. Vishik

Topological Insulator-to-Weyl Semimetal Transition in Strongly Correlated Actinide System UNiSn