对磁性多层膜中自旋流的产生、输运与检测进行深入研究，提高自旋流的产生和探测效率，研究自旋流的输运规律，将有助于设计、构建新型的自旋流电子器件，对于自旋电子学研究的进一步发展、探索后摩尔时代新技术具有重要意义。本项目申请将：（1）利用铁磁共振自旋泵浦效应和温度梯度自旋塞贝克效应两种实验方法研究自旋流从铁磁层向非磁层的稳态注入，探索铁磁/非磁界面的自旋流注入机理以及界面自旋-轨道耦合作用如何影响自旋注入效率，正确标定磁性材料体系的自旋霍尔角和自旋扩散长度，寻找同时具有较大的自旋霍尔角和较长的自旋扩散长度的材料；（2）利用飞秒激光产生飞秒尺度超快自旋流，并利用超快太赫兹产生实现超快自旋流的探测，研究磁性多层膜中超快自旋流的注入和输运规律，以及其与稳态自旋流传输规律的差异，探索新型超快自旋流-电荷流转换机制，提高超快太赫兹产生的效率，发现新型的超快自旋流的应用。

We plan to carry out the studies of the generation, transport and detection of the pure spin current, aiming for understanding its underlying mechanism and raise the efficiencies of the pure spin current generation and detection. The outline of our studies is described as: (1) combine the experimental approaches of spin pumping and spin Seeback effect to study the static injection of the pure spin current from ferromagnetic layer to nonmagnetic layer, unveil the pure spin current injection mechanism and understand the effects of spin-orbit coupling strength and interface roughness etc., on the spin injection; develop the methods to quantify the spin Hall angle and spin diffusion length, at the mean time, search for the high quality materials which have both large spin Hall angle and long spin diffusion length; (2) Utilize the ultrafast THz generation to probe the law of injection and transport of the ultrafast pure spin current generated by the femtosecond laser; find the similarity and differences between the static and ultrafast nonequilibrium pure spin current; raise the efficiency of the ultrafast THz generation and explore the new applications of the ultrafast pure spin current. These studies will be beneficial for design and construction of the pure spin current based novel low-power spintronic devices and will make an important step for exploring the next generation information technology in the coming post-Moore era.