SFB 1170: Topological and Correlated Electronics at Surfaces and Interfaces ("ToCoTronics")

关于“表面和界面的拓扑和关联电子学”的SFB 1170旨在结合现代凝聚态物理中最活跃和最令人兴奋的两个领域：物质的拓扑相和强电子关联。近年来，这两个领域的结合，特别是由于自旋-轨道相互作用和强电子关联的存在而产生的物理学正朝着令人兴奋的方向发展。在前几个资助时期，我们实现了重大科学突破。其中最主要的例子是：测量拓扑约瑟夫森结中的4PI周期约瑟夫森超导电流，确定拓扑晶体绝缘体(Pb，Sn)Se中的自旋极化中间能隙状态，发现铋作为一种新型的量子自旋霍尔材料，发现反铁磁性拓扑绝缘体MnBi2Te4，发现铟作为实空间受阻拓扑绝缘体，确定两种互补材料(Bi和HgTe)中相互作用的螺旋边缘态，以及预测相关的Kagome材料。我们主要研究人员的这些和其他成果为三个项目领域的进一步研究发展提供了理想的种子：(A)拓扑绝缘体；(B)混合系统和拓扑超导；(C)关联电子系统中的自旋-轨道耦合。我们现在能够在第三个资助期解决以下研究问题。首先，我们的目标是使用已建立的拓扑材料(如HgTe)来探索新的现象和器件。其次，我们计划设计和合成高质量的新型拓扑材料(如MnBi2Te4或元素原子单分子膜)。第三，我们将对Kagome金属/超导体的研究添加到我们的研究议程中。在光谱学方面，我们计划研究拓扑物质边界态的特殊电荷、自旋和轨道性质。就电子和热输运而言，我们的目标是了解极限散射机制。超导混合结构在第三个资助期的研究目标中扮演着重要的角色。重点研究了具有Andreev束缚态、Yu-Shiba-Rusinov态和Majorana零模等新束束态的拓扑超导电性。此外，我们计划预测和开发强关联的拓扑系统，例如，基于Kagome金属或复合氧化物。从基础物理的角度，我们的目标是深入了解多体物理和拓扑学的相互作用。从更实用的角度来看，我们的目标是预测和实现拓扑物质的创新设备概念，例如与自旋电子学和量子计算相关的概念。

The SFB 1170 on “Topological and Correlated Electronics at Surfaces and Interfaces” aims at combining two of the most active and exciting fields of modern condensed matter physics: topological phases of matter and strong electronic correlations. In recent years, the combination of the two fields, in particular, the emergent physics due to the presence of both spin-orbit interaction and strong electronic correlations develops in exciting directions. In the previous funding periods, we have accomplished major scientific breakthroughs. Prime examples thereof are: measurement of a 4pi-periodic Josephson supercurrent in topological Josephson junctions, identification of spin-polarized midgap states in the topological crystalline insulator (Pb,Sn)Se, discovery of bismuthene as a novel quantum spin Hall material, discovery of the antiferromagnetic topological insulator MnBi2Te4, discovery of indenene as a real-space obstructed topological insulator, identification of interacting helical edge states in two complementary materials (Bi and HgTe), and prediction of correlated kagome materials. These and other achievements of our principal investigators constitute ideal seeds for further research developments in the three project areas: (A) Topological insulators; (B) Hybrid systems and topological superconductivity; (C) Spin-orbit coupling in correlated electron systems. We are now in the position to address the following research questions in the third funding period. First, we aim to explore both new phenomena and devices using established topological materials (such as HgTe). Second, we plan to design and synthesize new topological materials of high quality (such as MnBi2Te4 or elemental atomic monolayers). Third, we add the investigation of kagome metals/superconductors to our research agenda. Spectroscopically, we plan to investigate particular charge, spin and orbital properties of the boundary states of topological matter. As far as electron and heat transport is concerned, we aim to understand the limiting scattering mechanisms. Superconductor hybrid structures play an important role in the research objectives of the third funding period. The focus is put on a thorough study of topological superconductivity with emerging bound states such as Andreev bound states, Yu-Shiba-Rusinov states, and Majorana zero modes. Moreover, we plan to predict and develop strongly correlated topological systems, for instance, based on kagome metals or complex oxides. From a fundamental physics perspective, we aim to understand deeply the interplay of many-body physics and topology. From a more applied point of view, we target at the prediction and realization of innovative device concepts of topological matter, for instance, related to spintronics and quantum computing.