光-磁相互作用的超快过程研究，是发展高速磁存储器的前提。飞秒激光技术的发展为此提供了研究手段，超快自旋动力学研究已成为国际前沿热点。然而激光脉冲激发自旋电子学材料后，电子、自旋、轨道和晶格之间相互作用的退磁物理过程还没有研究清楚，特别是自旋角动量耗散途径存在很大争议。本项目拟以飞秒时间分辨超快光谱为技术手段，结合金刚石对顶砧高压技术，通过压力调控环状磁性隧道结的自旋动力学，探讨超快激光脉冲激发条件下电子、自旋、晶格等之间的相互作用，并解释其自旋角动量的耗散途径。通过外加电场调控自旋输运，改变激发光的偏振方向，激发强度等因素，揭示不同结构铁磁材料与环状磁性隧道结的超快退磁机理和自旋弛豫途径。我们的研究将为探索新型自旋电子学材料提供实验支持，提高我国在超快自旋电子学等研究领域的国际影响力。

Ultrafast dynamics of magneto-optical interaction is the prerequisite for the development of high-speed magnetic memory. Development of femtosecond laser technology aims to provide a research tool, study of ultrafast spin dynamic has become an international frontier research hotspots. However, after the laser pulse excitation of the spin electronics materials, the demagnetization physical process of interaction between electron, spin, orbital and lattice has not been studied well, especially the dissipative channels of spin angular momentum. This project is intended to use femtosecond time-resolved ultrafast spectroscopy techniques combined with high pressure Diamond Anvil Cell technology，discuss the interaction among electron, spin and lattice under ultrafast laser pulses excitation by changing the pressure to regulate the spin dynamics of nanoring magnetic tunnel junctions, further explore the dissipation channel of spin angular momentum. We aim to reveal ultrafast demagnetization mechanism and spin relaxation path of different ferromagnetic materials and nanoring magnetic tunnel junctions by control of spin transport through an applied electric field and changing the polarization direction and intensity of the excitation light. Our study will provide experimental support for exploring a new type of spin electronics materials, to enhance our international influence in the research fields of ultrafast spin electronics.