亚100nm铁纳米点的磁指纹
Magnetic Fingerprints of sub-100 nm Fe Nanodots
摘要：
亚100 nm纳米磁体不仅在技术上是重要的，而且由于它们的尺寸与典型的磁畴壁宽度相当，因此表现出复杂的磁化反转行为。在这里，我们捕获磁性“指纹”的10亿铁纳米点，因为他们经历了一个单一的域涡旋状态的转变，使用一阶反转曲线（FORC）的方法。随着纳米点尺寸从52 nm增加到67 nm，FORC图显示出惊人的差异，尽管它们的主要磁滞回线只有细微的变化。52 nm纳米点表现出单畴行为，并且从FORC分布中提取的矫顽力分布与基于测量的纳米点尺寸分布的计算吻合得很好。58和67 nm纳米点表现出涡旋状态，其中涡旋的成核和湮灭表现为FORC分布中的蝴蝶状特征，并通过微磁模拟证实。此外，FORC方法给出了磁相分数的定量测量，以及涡旋成核和湮灭场。
英文摘要：
Sub-100 nm nanomagnets not only are technologically important, but also exhibit complex magnetization reversal behaviors as their dimensions are comparable to typical magnetic domain wall widths. Here we capture magnetic "fingerprints" of 1 billion Fe nanodots as they undergo a single domain to vortex state transition, using a first-order reversal curve (FORC) method. As the nanodot size increases from 52 nm to 67 nm, the FORC diagrams reveal striking differences, despite only subtle changes in their major hysteresis loops. The 52 nm nanodots exhibit single domain behavior and the coercivity distribution extracted from the FORC distribution agrees well with a calculation based on the measured nanodot size distribution. The 58 and 67 nm nanodots exhibit vortex states, where the nucleation and annihilation of the vortices are manifested as butterfly-like features in the FORC distribution and confirmed by micromagnetic simulations. Furthermore, the FORC method gives quantitative measures of the magnetic phase fractions, and vortex nucleation and annihilation fields.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
