空中骑兵
纳米柱
凝聚态物理
物理
自旋(空气动力学)
旋转(数学)
扭矩
反铁磁性
微磁学
旋转
联轴节(管道)
材料科学
纳米结构
磁场
量子力学
磁化
几何学
热力学
数学
冶金
作者
Sai Zhou,Cuixiu Zheng,Xing Chen,Yaowen Liu
摘要
The skyrmion-based spin-torque nano-oscillator is a potential next-generation nano microwave signal generator. In this paper, the self-sustained oscillation dynamics of magnetic skyrmions are investigated in a nanodisk with synthetic antiferromagnetic (SAF) multilayer structure, in which the skyrmion Hall effect can be effectively suppressed. An analytical model based on the Thiele equation is developed to describe the dynamics of a pair of skyrmions formed in the SAF nanodisks. Combining the analytical solutions with the micromagnetic simulations, we demonstrate that circular rotations with opposite directions for a skyrmion pair could be suppressed by increasing the antiferromagnetic (AF) coupling in a nanopillar with dual spin polarizers. However, a stable circular rotation can be achieved in a nanopillar with a single spin polarizer, in which one skyrmion plays as a master whose rotation is driven by spin torque, while the other skyrmion is a slaver whose motion is dragged by the AF coupling between the two free layers. Moreover, we found that the effective mass factor in the SAF structure rather than the gyrotropic torque plays the dominant role in the circular rotation of skyrmions. The rotation orbit radius and frequency gradually increase with the decrease of damping factor and increase of applied current strength.
科研通智能强力驱动
Strongly Powered by AbleSci AI