非磁金属/铁磁金属异质结构中自旋力矩铁磁共振的微观理论
Microscopic theory of spin-torque ferromagnetic resonance in nonmagnetic-metal/ferromagnetic-metal heterostructures
- Advanced Science Research Center, Japan Atomic Energy Agency（日本原子力机构先进科学研究中心）
- Institute for Solid State Physics, University of Tokyo（东京大学固体离子体研究所）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文提出微观理论，推导界面交换耦合，计算ST-FMR谱，揭示其反映相邻电子系统的自旋响应，建立统一框架。
AI中文摘要：
我们发展了非磁金属/铁磁金属异质结构中自旋力矩铁磁共振（ST-FMR）的微观理论。通过追踪铁磁体中传导电子自由度，我们推导出局域自旋与相邻电子系统中传导电子自旋之间的有效界面交换耦合。基于该相互作用，我们计算了电流诱导的驱动力矩、共振频移、阻尼调制以及由此产生的直流电压。作为具体实例，我们将该公式应用于无序的Rashba二维电子气，并证明ST-FMR谱反映了相邻电子系统的动力学自旋响应。我们的公式适用于广泛类别的异质结构，并建立了一个统一的微观框架，将ST-FMR谱直接与相邻系统的电子自旋响应联系起来。
英文摘要：
We develop a microscopic theory of spin-torque ferromagnetic resonance (ST-FMR) in nonmagnetic-metal/ferromagnetic-metal heterostructures. Tracing out the conduction-electron degrees of freedom in the FM, we derive an effective interfacial exchange coupling between the localized spins and the conduction electron spins in the adjacent electron system. Based on this interaction, we calculate the current-induced driving torque, resonance-frequency shift, damping modulation, and resulting dc voltage. As a concrete example, we apply the formulation to a disordered Rashba two-dimensional electron gas and demonstrate that the ST-FMR spectrum reflects the dynamical spin responses of the adjacent electron system. Our formulation applies to a broad class of heterostructures and establishes a unified microscopic framework connecting ST-FMR spectra directly to the electronic spin responses of adjacent systems.
