Abstract Narrow magnetic domain walls in rectangular nanowires with perpendicular anisotropy are a vital component for many spintronic devices. Probing the structure of the domain wall is interesting for applications, and it also provides a means to accurately determine fundamental material parameters, such as the size of the Dzyaloshinskii-Moriya interaction strength. The domain wall structure can be inferred using a variety of recent, novel experiments that measure the stray field above the magnetic wire, but the interpretation of these measurements requires an accurate theoretical method that relates the stray field to the magnetic structure. Here, various one-dimensional analytic methods for finding stray field are compared to MuMax simulations in order to determine if there exists an accurate analytic way to interpret a wide range of experiments. This has the advantage of being fast and simple compared to numerical simulations. Our analytic method relies on approximating the domain wall profile as a piecewise, linear function. It is shown to be accurate for parameters appropriate to CoPtCr nanowires that are 3 nm thick and 40-100 nm wide, and is expected to work broadly for nanowires that are thinner than the exchange length.

中文翻译：

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矩形纳米带中 Néel 和 Bloch 磁畴壁上方杂散场的解析计算

摘要 具有垂直各向异性的矩形纳米线中的窄磁畴壁是许多自旋电子器件的重要组成部分。探测畴壁的结构对于应用来说很有趣，它还提供了一种准确确定基本材料参数的方法，例如 Dzyaloshinskii-Moriya 相互作用强度的大小。磁畴壁结构可以使用各种最近测量磁线上方杂散场的新颖实验来推断，但对这些测量的解释需要一种准确的理论方法，将杂散场与磁结构联系起来。这里，将用于寻找杂散场的各种一维分析方法与 MuMax 模拟进行比较，以确定是否存在解释各种实验的准确分析方法。与数值模拟相比，这具有快速和简单的优点。我们的分析方法依赖于将畴壁轮廓近似为分段线性函数。它被证明对于适用于 3 nm 厚和 40-100 nm 宽的 CoPtCr 纳米线的参数是准确的，并且有望广泛适用于比交换长度更细的纳米线。