Abstract Magnetic skyrmions have been proved to be applicable to spin torque nano-oscillator. In this paper, we show dynamics of magnetic skyrmions in elliptical spin-valve nanopillar with perpendicular magnetic anisotropy (PMA) free layer and spin polarizer by using micromagnetic simulation. A novel semi-skyrmions-based oscillation mode with GHz frequencies appears in this geometry. We find that the mode frequencies strongly depend on the in-plane dimension of the elliptical nanopillar. The fitting function between the mode frequency and the perimeter of the ellipse is obtained. Simulation results also show that the exchange constant and the temperature effect have great influence on the mode frequency.

中文翻译：

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具有垂直各向异性的椭圆纳米柱中基于半斯格明子的振荡器

摘要 磁性斯格明子已被证明适用于自旋力矩纳米振荡器。在本文中，我们通过使用微磁模拟展示了具有垂直磁各向异性 (PMA) 自由层和自旋偏振器的椭圆自旋阀纳米柱中磁性斯格明子的动力学。在这种几何结构中出现了一种具有 GHz 频率的基于半斯格明子的新型振荡模式。我们发现模式频率强烈依赖于椭圆形纳米柱的平面尺寸。得到模态频率与椭圆周长的拟合函数。仿真结果还表明，交换常数和温度效应对模式频率有很大影响。