对称失配关联电子异质界面磁性新物态设计与高效调控

关联电子磁性氧化物具有常规材料所没有的一些重要特征，其量子演生现象的研究可能导致面向未来的新原理、新材料与新技术。以往研究多集中于相同结构氧化物的异质界面，界面重整效应受限。利用对称性不同，但结构框架和拓扑关系类似的氧化物构成对称失配异质外延界面，将强化界面重构效应，充分利用关联电子体系多自由度关联特征。基于以上考虑，本项目建议研究：对称失配关联电子异质界面磁性新物态设计与高效调控，拟利用对称失配下异质界面自旋关联、轨道再构、电荷重组，设计新型界面自旋电子态，探索：（1）具有常规体系中不存在的新自旋结构，例如具有特定取向的自旋态、自旋结构如拓扑/涡旋自旋结构及其它新型自旋物态；（2）自旋输运可控及电荷输运特性优异的新材料体系；（3）自旋电子态的高效调控新途径。通过本项目的研究，希望拓展量子材料及相关效应研究的新空间，获得对关联电子磁性相关问题的深刻认识，实现对自旋电子态的自主设计与调控。

Different from conventional materials, electron-correlated magnetic oxides have a few intriguing properties that lead to many exotic quantum emergent phenomena. The study of these phenomena is very promising for future device applications with new principles, new materials, and new technologies. However, most of previous works in this field focus only on heterostructures made from oxides with the same lattice structure, typically perovskite structure. While this choice is good for achieving interfaces with ideal crystalline structure, it weakens the effect of interface reconstruction of spin, charge and orbital, which is adverse for the occurrence of interface emergent phenomena. In order to enhance interface reconstruction, symmetry-mismatched interfaces are highly desirable. In this project, by constructing high-quality symmetry-mismatched heterostructures, we aim to explore new interface magnetic states, and the ways to efficiently tune these states. We will design new type interface spin states by utilizing the symmetry-mismatch-induced spin coupling, orbital reconstruction, and charge redistribution. Special attentions will be paid to the following three topics: (1)new spin structures that are absent in normal materials, such as spin states with a particular orientation, topological or vortex spin structures, or other new structures; (2) new material systems that show excellent electrical transport properties and controllable spin transport;(3) new ways to efficiently tune interface spin states. The goal of this project is to expand scope for the study of quantum materials and their relevant effects, obtain better understanding on a few fundamental questions of magnetism in electron-correlated systems, and finally achieve successful designing and tuning of interface spin states.