Dependence of domain wall pinning potential landscapes on domain wall chirality and pinning site geometry in planar nanowires
Dependence of domain wall pinning potential landscapes on domain wall chirality and pinning site geometry in planar nanowires
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DOI：
10.1103/physrevb.79.054414
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发表时间：
2009-02-01
影响因子：
3.7
通讯作者：
McVitie, S.
中科院分区：
文献类型：
--
作者：
Bogart, L. K.;Atkinson, D.;McVitie, S.
我们报告了平面坡莫合金纳米线中两种不同几何形状的凹口产生的畴壁钉扎行为和势能景观。使用空间分辨磁光克尔效应测量对畴壁脱钉进行了实验探测。使用洛伦兹显微镜确定了钉扎畴壁的自旋结构，并使用微磁模拟分析了畴壁钉扎行为，这与实验结果具有良好的定性一致性。所有凹口结构的尺寸都与畴壁长度尺度相当。对于所研究的缺口结构，发现畴壁经历的脱钉场对缺口几何形状相对不敏感，尽管钉扎行为对壁类型和壁手性自旋结构高度敏感。从能量上讲，凹口呈现势垒和/或势阱，具体取决于畴壁的微磁结构，我们发现畴壁的手性是钉扎势景观的关键决定因素。详细讨论了畴壁的钉扎行为，并对钉扎在三角形和矩形凹口中的涡流壁给出了负责畴壁钉扎的势阱和/或势垒的宽度和深度的直接定量测量。
We report on domain wall pinning behavior and the potential-energy landscapes created by notches of two different geometries in planar Permalloy nanowires. Domain wall depinning was probed experimentally using spatially resolved magneto-optical Kerr effect measurements. The spin structure of pinned domain walls was determined using Lorentz microscopy, and domain wall pinning behavior was also analyzed using micromagnetic simulations, which are in good qualitative agreement with experimental results. All notch structures have dimensions that are comparable with the domain wall length scales. For the notch structures investigated, the depinning field experienced by a domain wall is found to be relatively insensitive to notch geometry although the pinning behavior is highly sensitive to both the wall type and the wall chirality spin structure. Energetically, the notches present both potential barriers and/or potential wells depending on the micromagnetic structure of the domain wall, and we find that the chirality of the domain wall is a key determinant of the pinning potential landscape. The pinning behavior of domain walls is discussed in detail, and direct quantitative measurements of the width and depth of the potential wells and/or barriers responsible for domain wall pinning are given for vortex walls pinned in triangular and rectangular notches.