自旋轨道耦合莫特绝缘体的量子磁性调控

In recent years a new class of materials, known as spin-orbit Mott insulators, has captured the interest of many physicists. Their electronic structure is unlike anything we have seen before as it combines a strong Coulomb repulsion with a large relativistic spin-orbit interaction. This unprecedented energy landscape creates favourable conditions for exciting new phenomena such as topological phases, quantum magnetism and superconductivity. The prime goal of this research plan here is to investigate and control electronic and magnetic phases, arising from electronic and orbital reconstruction at hetero-interface in spin-orbit Mott insulators. The concrete research plans are (i)to use first principles electronic structure calculations to study heterostructures with spin-orbit Mott insulator, understand the atomic structures and stability of complex interfaces, investigate the physics under spin-orbit coupling,and manipulate the quantum magnetism.(ii)construct BaTiO3/BaOsO3/BaTiO3 heterostructures and realize the giant,switchable Rashba effect by controlling the strengh of inversion symmetry broken. (iii)extend the single site DMFT to multilayer DMFT methods intended for calculations of strongly correlated heterostructures, and develop DFT+SOC+DMFT methods for 5d transition metal oxide heterostructures. This project will lay the foundations for the use of spin-orbit Mott insulators as a new platform for topological phases in condensed-matter.

本项目从自旋轨道耦合莫特绝缘体异质界面的原子结构、电子结构的层面出发，研究异质界面的电输运性质和量子磁性调控，探索强自旋轨道耦合、电子关联、晶体场等作用机制，揭示外延应力、外电场的调控规律，为实现5d过渡金属氧化物在下一代量子器件中的潜在应用提供理论基础和技术路径。采用基于密度泛函的第一性原理计算方法研究自旋轨道耦合莫特绝缘体的量子磁性，构建氧化物异质结构，通过外延应力、电场等手段调控磁性；通过构建BaTiO3/BaOsO3/BaTiO3异质结构，利用铁电畸变提供异质结较大的空间反演对称性破缺强度，从而在5d过渡金属氧化物异质界面实现巨大、可控的Rashba效应，探索氧化物异质结在自旋电子器件中的技术应用；发展和完善处理强关联电子体系的计算方法，发展DFT+SOC+DMFT方法研究强自旋轨道耦合的关联氧化物异质结。

本项目从自旋轨道耦合莫特绝缘体异质界面的原子结构、电子结构的层面出发，研究了异质界面的电输运性质和量子磁性调控，探索强自旋轨道耦合、电子关联、晶体场等作用机制，揭示外延应力、外电场的调控规律，为实现5d过渡金属氧化物在下一代量子器件中的潜在应用提供理论基础和技术路径。采用基于密度泛函的第一性原理计算方法研究自旋轨道耦合莫特绝缘体的量子磁性，构建氧化物异质结构，通过外延应力、电场等手段调控磁性；通过构建BaTiO3/BaOsO3/BaTiO3异质结构，利用铁电畸变提供异质结较大的空间反演对称性破缺强度，从而在5d过渡金属氧化物异质界面实现巨大、可控的Rashba效应，探索氧化物异质结在自旋电子器件中的技术应用；将DFT+DMFT的方法用来处理强关联电子体系，发展了DFT+SOC+DMFT方法研究强自旋轨道耦合的关联氧化物异质结；通过自行搭建的激光分子束外延生长设备和自主设计的“高分辨质量选择团簇束流实验装置及在线催化测试”实验系统，实验探索研究了低维5d过渡金属氧化物系统的奇异物性。