拓扑绝缘体/垂直磁化3d铁磁界面自旋输运研究

基于拓扑量子材料的自旋输运是凝聚态物理特别是自旋电子学的研究前沿，对于实现后摩尔时代的低功耗量子自旋电子器件具有重要意义。特别地，拓扑量子材料中的拓扑绝缘体具有鲁棒性以及新颖的自旋-角动量锁定效应，可以实现高效电荷流-自旋流相互转化。当前，关于拓扑绝缘体与3d磁性层异质结的制备、物性研究尚处于初步探索阶段，众多材料和物理问题有待研究。在本项目中，我们拟利用磁控溅射技术制备Bi2Te3、Bi2Se3、Sb2Te3等拓扑绝缘体材料，并与具有垂直磁各向异性的3d铁磁金属(Fe、Co、Ni)形成异质结构，研究界面结构对于自旋输运的影响机制，揭示自旋轨道矩驱动磁矩翻转的物理特性，厘清拓扑表面态、界面Rashba效应以及自旋霍尔效应对自旋输运的影响，为实现高稳定性、高兼容性、低功耗的新一代拓扑自旋电子器件提供指导。

Spin transport in topological materials emerges as the research frontier of condensed matter physics (especially of spintronics), which shows great prospect for low power consumption quantum spintronic devices in the post-Moore era. More remarkably, the topological insulator (TI) exhibits robust electron transport and intriguing spin-momentum locking effect, enabling highly efficient interconversion between charge and spin currents. However, the studies on the material and physics characteristics of TI/3d ferromagnet are still preliminary, requiring more explorations from both the material and physics aspects. In this project, we will utilize magnetron sputtering to fabricate TI materials such as Bi2Te3, Bi2Se3 and Sb2Te3, and subsequently deposit 3d ferromagnet (FM) to form TI/3d FM heterostructures with perpendicular magnetic anisotropy. In the perpendicularly magnetized TI/3d FM heterostructures, this project will focus on: (1) Investigating the influence of interfacial structure on the spin transport. (2) Revealing the physical characteristics of SOT driven magnetization switching. (3) Quantifying the contributions from different physical mechanisms such as the topological surface state, the interfacial Rashba effect and bulk spin Hall effect in the spin transport of TI/3d FM. These studies will pave important foundation for realizing new generation topological spintronic devices with high stability, high compatibility and low power consumption.