Yuan X, Lu Z, Li S, Fan S, Wang G, Fang X, Xiong R
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, People's Republic of China. School of Materials and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, People's Republic of China.
Nanotechnology. 2020 Aug 21;31(34):345709. doi: 10.1088/1361-6528/ab91f5. Epub 2020 May 11.
In this paper, the magnetization dynamics of bilayer structured nano-pillars containing a fixed layer with perpendicular magnetic anisotropy (PMA) and a free layer with in-plane magnetic anisotropy (IMA) are studied using the micro-magnetic simulation method. Unlike typical sandwich-structured spin-torque nano-pillar oscillators (STNOs), the proposed structure does not contain any nonmagnetic spacer layer. It is found that a stable oscillation with a significant amplitude can be established fast after driving out the vortex core by an in-plane magnetic pulse field. The oscillation frequency and amplitude can be easily manipulated by adjusting the side-length of the nanopillar, the thickness and saturation magnetization of the IMA layer, and an applied magnetic field along z axis. In an array with an adequate inter-pillar distance, the mutual interaction between the nano-pillars will lead the oscillations to be phase-locked, resulting in a considerable enhancement of total amplitude. As it is easy to fabricate these kinds of bi-layer nano-pillars and assemble them in arrays, they may have widespread applications in STNOs.
在本文中，使用微磁模拟方法研究了双层结构纳米柱的磁化动力学，该双层结构纳米柱包含具有垂直磁各向异性（PMA）的固定层和具有面内磁各向异性（IMA）的自由层。与典型的三明治结构自旋扭矩纳米柱振荡器（STNO）不同，所提出的结构不包含任何非磁性间隔层。研究发现，通过面内磁脉冲场驱出涡旋核心后，可以快速建立具有显著幅度的稳定振荡。通过调整纳米柱的边长、IMA层的厚度和饱和磁化强度以及沿z轴施加的磁场，可以轻松控制振荡频率和幅度。在具有足够柱间距的阵列中，纳米柱之间的相互作用将导致振荡锁相，从而使总幅度得到显著增强。由于这类双层纳米柱易于制造并组装成阵列，它们可能在STNO中具有广泛的应用。
