强磁场下二维薄层磁性材料的超快自旋动力学研究

二维薄层磁性材料由于其丰富物理内涵及在低维自旋电子器件中的应用前景，已成为了当前物理研究的焦点。前期研究已经发现了诸如界面耦合、隧道磁阻、磁控发光等奇异的静态量子现象，但其二维磁性的自旋动力学探测与调控依然有待探索。作为一种极端条件的能量场，强磁场能有效调控物质的量子行为，激发新奇量子态；而强磁场下的超快光谱技术则是研究低维磁性材料动力学不可或缺的手段。本项目将分别以自上而下、自下而上两种方式获得二维薄层磁性材料；充分发挥合肥稳态强磁场装置中强磁场下超快光谱的技术优势，实现对两种二维薄层材料自旋量子态的超快探测与超快调控。一方面获得二维磁性体系中的动力学关键参数（比如超快自旋弛豫时间、自旋共振频率、吉尔伯特阻尼因子、朗德g因子等），另一方面实现对二维薄层中的超快自旋相干控制，获得调控窗口与相图，为二维高频自旋电子学器件的研发提供实验基础。

Two-dimensional thin-layer magnetic materials have become the focus of current physical research due to their rich physical properties and their potential application in low-dimensional spintronic devices. Earlier studies have discovered lots of quantum phenomena such as interface coupling, tunnel magnetoresistance, magnetron luminescence, etc. However, the dynamic behavior of two-dimensional magnetism and its mechanism remain to be explored. As an extreme condition, high magnetic field can effectively modulate the quantum behavior, excite novel quantum states, and ultrafast spectroscopy under a strong magnetic field is an indispensable tool in studying the dynamics of low-dimensional magnetic materials. This project will focus on two kinds of two-dimensional thin-layer magnetic materials, which are obtained by top-down and bottom-up fabrication methods respectively. Taking the advantages of strong magnetic fields and ultra-fast magneto-optic spectroscopy techniques in High Magnetic Field Laboratory, CAS, the spin dynamics of two kinds of two-dimensional thin layers will be studied, including ultrafast detection and ultrafast modulation of the spin quantum state of layer materials. On the one hand, the key dynamic parameters, such as ultrafast spin relaxation time, spin resonance frequency, Gilbert damping factor, Lande g factor, etc., of the two-dimensional magnetic system will be obtained. On the other hand, the ultra-fast spin coherent control in the system will be realized and the controlling parameters window and phase diagram will be obtained. These results should provide experimental basis for the development of two-dimensional high-frequency spintronics devices.