Ab-initio discovery of high-temperature topological magnetic materials

自从最初发现拓扑绝缘体以来，在理论设计和材料研究的指导下，发现了大量的拓扑电子相。虽然在拓扑材料中，磁性材料的一个子类可能是该领域最令人兴奋的新思想的出口，但迄今为止，实现各种时间反转的破缺拓扑相的进展相当缓慢。这可能与在高温下表现出稳定磁性和稳定量子化磁输运特性的最佳磁性材料迄今尚未设计出来有关。通过我们的联合项目——这是一个紧密结合的中德合作项目，北京团队的私家侦探冯万祥和姚玉贵，美因茨团队的私家侦探Yuriy Mokrousov和Jairo Sinova——我们将解决这一挑战。借助该联盟已经积累并将进一步发展的理论工具，我们将致力于从理论上发现在电子结构和临界温度方面具有优化性能的新型磁性拓扑材料。我们将预测拓扑磁体中可能出现的各种拓扑相，并根据对对称性、拓扑、结构和磁性手性以及热波动的相互作用敏感的已知和新的线性和非线性输运效应，提出表征它们的方法。我们将大致描绘出磁性材料在高温下复杂拓扑相的出现和行为，从而在拓扑自旋电子学领域取得质的飞跃，并为拓扑磁性的实验探索奠定基础。

Since the initial discovery of topological insulators, a plethora of topological electronic phases was uncovered, guided by theoretical design and materials research. While among topological materials, a subclass of magnetic materials is perhaps the most exciting outlet for novel ideas in the field, the progress in realization of various time-reversal broken topological phases has been so far quite slow. This can be associated with the fact that optimal magnetic materials which exhibit stable magnetism and stable quantized magneto-transport properties at high temperatures have not been designed to date. With our consortium project - which is a closely entangled Sino-German effort comprising Wanxiang Feng and Yugui Yao as PIs of the Beijing team, and Yuriy Mokrousov and Jairo Sinova as PIs of the Mainz team - we will address this challenge. With the help of theoretical tools that the consortium has accumulated and will develop further, we will aim at a theoretical discovery of novel magnetic topological materials which have optimized properties in terms of their electronic structure and critical temperatures. We will predict a variety of topological phases that can arise in topological magnets and suggest the means of their characterization in terms of known and novel linear and non-linear transport effects sensitive to the interplay of symmetry, topology, structural and magnetic chirality, and thermal fluctuations. We will draw a general picture of the emergence and behavior of complex topological phases in magnetic materials at high temperatures, thereby making a qualitative leap forward in the area of topological spintronics, and laying a foundation for experimental exploration of topological magnetism.