Chiral Strain Engineering of Polar Semiconductors

非技术描述手性是一个描述物体(如晶体、分子或电子自旋和动量之间的关系)的概念，它具有与其镜像不同的结构，在推动材料物理中的许多基本现象方面发挥着关键作用。晶态手性固体表现出独特的自旋-动量关系和强大的手性诱导自旋选择性，使其在室温下进行高能效的自旋电子计算具有很好的应用前景。提出的手性弹性应变工程方法为探索和发现新的手性材料和相提供了一个框架。这种方法不仅可以丰富对手性电子性质及其与应变关系的基本认识，而且有可能加速手性材料在未来的自旋电子学和计算技术中的应用。该奖项还旨在促进各类学生的科学和工程教育和研究培训，包括来自该领域历史上代表性不足的群体的学生，这些学生的主题是手性电子材料。技术描述在拓扑绝缘体、Weyl半金属和Rashba/Dresselhaus晶体/系统的表面状态中观察到的手性自旋-轨道耦合，在集成量子光子学和电子学的新兴光子和自旋电子器件的设计中起着至关重要的作用。手性晶体具有Kramers-Weyl手性自旋-轨道耦合，可以是金属也可以是绝缘体，与拓扑绝缘体或Weyl半金属相比，为拓扑上的非平凡行为提供了更大的能量窗口。此外，在手性材料中还发现了较强的室温手性诱导自旋选择性。然而，晶态手性半导体的可用性是有限的，这严重阻碍了选择合适的模型系统来研究Kramers-Weyl物理、手性电子输运性质以及基于手性材料的自旋电子器件的发展。在这个项目中，主要研究人员提出利用弹性应变将非手性半导体转变为具有拓扑手性电子结构的手性相。我们的目标是揭示手性特性和应变场之间的基本关系。我们还将研究电场在手性手性转换中的作用。该项目将促进对手性电子结构、电子传输、光学和光电子性质的基本理解，并将为未来的计算扩展关于手性自旋电子学性质和器件的材料数据库。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 descriptionChirality, a concept that describes objects (such as crystals, molecules, or the relationship between electron spin and momentum) that possess a distinct configuration from their mirror image, plays a pivotal role in driving many fundamental phenomena in materials physics. Crystalline chiral solids exhibit a unique spin-momentum relation and robust chiral-induced spin selectivity, making them highly promising for energy-efficient spintronic computing at room temperature. The proposed approach of chiral elastic strain engineering offers a framework that facilitates the exploration and discovery of new chiral materials and phases. This approach not only enables the enriching of basic understanding of chiral electronic properties and their relations with strain, but also has the potential to accelerate the implementation of chiral materials in future spintronics and computing technologies. This award also aims to promote science and engineering education and research training among a diverse range of students, including those from historically underrepresented groups in the field, on the topic of chiral electronic materials. The results gained from this award will contribute to the advancement of future microelectronics, benefiting the overall societal progress of the United States.Technical descriptionChiral spin-orbit coupling, observed in the surface states of topological insulators, Weyl semimetals, and Rashba/Dresselhaus crystals/systems, plays a crucial role in the design of emerging photonic and spintronic devices for integrated quantum photonics and electronics. Chiral crystals, featuring Kramers-Weyl chiral spin-orbit coupling, can be either metals or insulators, providing a larger energy window for topologically non-trivial behavior compared to topological insulators or Weyl semimetals. Moreover, robust room temperature chiral-induced spin selectivity has been discovered in chiral materials. However, the availability of crystalline chiral semiconductors is limited, which significantly hinders the selection of suitable model systems for studying Kramers-Weyl physics, chiral electronic transport properties, and the development of spintronic devices based on chiral materials. In this project, the principal investigator proposes to utilize elastic strain to transform non-chiral semiconductors into chiral phases that possess topological chiral electronic structures. The goal is to uncover the fundamental relationship between chiral properties and strain fields. The role of electric fields in switching chiral handedness will also be investigated. This project will advance the fundamental understanding of chiral electronic structures, electronic transport, optical and optoelectronic properties, and will expand the materials database concerning chiral spintronic properties and devices for future computing.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.