具有尺寸限制的点接触结构自旋极化电流驱动下磁涡旋的稳态振荡

Steady Oscillations of Magnetic Vortex Driven by a Spin-Polarized Current in a Confined Point-Contact Structure

选取具有尺寸限制的点接触结构作为研究对象,采用Thiele方程对模型中磁涡旋在自旋极化电流作用下的动力学行为进行计算.计算表明磁涡旋可以在一定的电流密度范围内稳定旋转,该稳定旋转可以存在的电流密度范围与点接触区的大小和纳米点的尺寸有关.当磁涡旋核作稳态旋转时,其所处的轨道半径以及旋转频率都随电流密度的增加而增加,旋转频率可调节的范围随点接触尺寸的增加快速减小.

We choose a confined point-contact geometry as research model. Steady-state oscillations of magnetic vortex driven by a spin-polarized current are calculated with analytical calculations based on Thiele＇s equation. It indicates that magnetic vortex can maintain steady oscillations in a specific current range. Current density range depends on nanocontact dimensions and dot aspect ratios. Both orbital radius and frequency of steady oscillations increases with current density. Adjustable range of oscillation frequency decreases dramatically with increasing nanoeontaet size.