交换耦合磁性多层膜及隧道结中SOT效应和磁矩翻转研究

自旋轨道力矩(SOT)效应为通过纯电学手段操控磁矩提供了一种可行的物理机制。而且相比自旋转移力矩(STT)效应，SOT效应通过面内电流来实现磁矩的操控，因而比前者更适合开发基于磁性隧道结的长寿命和高可靠性的磁随机存储器(MRAM)，也是开发下一代高速非易失性随机存储器的关键技术。本项目拟在具有磁耦合效应的磁性多层膜及隧道结中，研究SOT驱动的磁矩翻转行为，获得可在零磁场条件下实现纯电流磁矩翻转且兼容MgO隧道结工艺的薄膜材料体系和SOT-MRAM原理型存储单元，并利用高速磁电输运测量技术测量自旋动力学参数，基于含时LLGS理论理解这些翻转行为。本项目可为研究SOT和磁耦合效应在磁耦合多层膜体系中对磁矩翻转过程的协同作用机制提供实验基础和理论解释，研制出高速、低功耗SOT-MRAM原理型存储单元，为后续SOT-MRAM开发提供合适的薄膜材料、器件结构、微加工工艺和知识产权。

Besides of spin-transfer torque, spin-orbit torque (SOT) provides a feasible mechanism to electrically manipulate spins, which can be further adopted in magnetic-tunnel-junction based magnetic random access memory with long lifetime and high reliability. SOT effect thus becomes a key toward next generation of nonvolatile memories. In this project, we aim to study SOT-driven spin dynamics and switching behaviors of magnetic multilayers and magnetic tunnel junctions with interlayer coupling effect inside and explain these switching behaviors in framework of Landau-Lifshitz-Gilbert- Slonczewski equation. In the end, if granted, this project can provide experimental bases to interpret synergistic action of SOT and magnetic coupling effect on magnetization switching dynamics, provide optimized magnetic film materials and device structures to develop high speed and low power SOT-MRAM prototype elementary device and also provide protection on intelligence properties for the development of practical SOT-MRAM devices.