First-principles modelling of spin transfer and magnetism at photo-excited two-dimensional magnets and van der Waals heterostructures

最近发现的二维(2D)磁体和与之相关的范德华(VDW)异质结构引起了人们对它们在原子尺度上操纵自旋或磁性的潜力的极大兴奋。光驱动的2D磁性和VDW异质结为探索新的物理和自旋电子应用提供了超快和非接触可调谐的可能性。该项目的目的是揭示光致层间自旋转移的微观机制，并基于实时含时密度泛函理论探索各种2D磁体和VDW异质结中的超快光学控制磁性质。首先研究了2D磁体和VDW异质结的基态性质，包括结构、电学、磁学和光学性质。然后，我们将对光激VDW耦合磁界面层间超快自旋相关的电荷转移过程有一个基本的理解，重点是磁序和自旋-轨道耦合的作用。同时，我们将在一些选定的磁性VDW系统中探索超快光致磁化方向的转换以及铁磁和反铁磁态之间的层间磁耦合。此外，还将重点研究层间旋转和平移的堆积顺序对2D磁体和VDW异质结的光致动力学的影响。

The recent discovery of two-dimensional (2D) magnets and the related van der Waals (vdW) heterostructures has generated a great deal of excitement over their potential for manipulation of spin or magnetism at the atomistic scale. Optically driving 2D magnetic and vdW heterostructures offer the possibility of ultrafast and noncontact tunability for exploring new physics and spintronic applications. The aim of the project is to unravel the microscopic mechanisms of photo-induced interlayer spin transfer, and explore ultrafast optical control magnetic properties in a large variety of 2D magnets and vdW heterostructures based on real-time time-dependent density functional theory. The ground-state properties of 2D magnets and vdW heterostructures, including structure, electronic, magnetic and optical properties will firstly be investigated. Then, we will develop a fundamental understanding for the interlayer ultrafast spin-dependent charge transfer process in photo-excited vdW-coupled magnetic interface with specific focus on the role of magnetic order and of spin-orbital coupling. In parallel, we will explore ultrafast light-induced switching of magnetization direction and interlayer magnetic coupling between ferromagnetic and antiferromagnetic states in some selected magnetic vdW system. Furthermore, the influence of stacking order through rotation and translation between the layers on the light-induced dynamics of 2D magnets and vdW heterostructures will be examined in particular.