自旋非共线反铁磁中新奇磁光效应及其多场调控研究

由于标量或矢量自旋手性的存在，自旋非共线反铁磁中涌现出很多新奇的物理现象，目前已经成为凝聚态物理中非常前沿的研究领域。磁光效应是磁性材料中一种基本的物理现象，既有丰富的物理内容，在磁性探测和磁光器件等方面也有着重要的应用前景。然而，目前对自旋非共线反铁磁中磁光效应的机理和应用还缺乏足够了解。本项目将基于第一性原理计算和紧束缚有效模型分析、同时结合实验测量来研究下面几个问题：（1）探索自旋非共线反铁磁中可能存在的新奇磁光效应，例如不需要自旋轨道耦合的拓扑磁光效应和量子化的拓扑磁光效应；（2）研究外场作用（电场、磁场和应变场）对自旋非共线反铁磁中磁光效应的影响，提出多场调控磁光效应的手段和方案；（3）寻找新的三维和二维自旋非共线反铁磁，并筛选性能优异的磁光宿主材料。通过本项目的研究，有望为磁光效应相关领域的进一步发展建立物理和材料基础。

Owing to the scalar or vector spin chirality, many exciting physical phenomena can emerge in noncollinear antiferromagnets (nc-AFM). So far, nc-AFM has already become a hot topic in the field of condensed matter physics. Magneto-optical (MO) effects, as the fundamental physical phenomena in magnetic materials, have not only abundant physical contents but also promising applications for magnetism exploring and MO devices. Nevertheless, there are not yet deep understandings about the physical origins and application modes of the MO effects in nc-AFM. In this project, using the first-principles calculations and effective tight-binding models, as well as experimental measurements, the following issues will be systematically investigated. (1) We will explore novel MO effects in nc-AFM, such as the topological MO effects without spin-orbit coupling and its quantum version. (2) We will study the influences of external fields (e.g., electric, magnetic, and strain fields) on the MO effects in nc-AFM and propose efficient approaches for the multiple-field-controlling of MO effects. (3) We will search new three- and two-dimensional nc-AFM and find out excellent MO candidates among them. This project will set up the theoretical and material foundations for further developments of MO-related fields.