Collaborative Proposal: Physics of Ferromagnetic Nanostructures in a Circular Field

* 技术摘要 * 这个霍利奥克山学院和阿默斯特的马萨诸塞州大学之间的合作项目，通过施加通过原子力显微镜尖端电流产生的局部圆形场，以及通过AFM尖端或样品上的制造引线施加电流脉冲，探索铁磁纳米结构中的磁态。 这些技术将允许单独控制磁盘的涡旋和涡旋核，以及操纵导线中的各个畴壁（DW），以研究不同类型DW的物理特性及其之间的相互作用。 足够薄的铁磁纳米环被预测具有独特的状态，包括对360度畴壁（DW）之间切换时，在所施加的圆形场的涡旋状态。 了解DW和圆形纳米结构将为下一代数据存储设备提供信息。 这项工作将涉及霍利奥克山学院的女本科生以及博士后和研究生，促进两个机构之间的频繁互动。 此外，将与K12教师和附近的斯普林菲尔德技术社区学院一起为既定项目开发有关磁性的课程材料，并将创建一个当地的科学咖啡馆，让科学和技术专家在非正式的环境中与公众交谈。非技术摘要 * 计算机硬盘驱动器目前以二进制位“1”和“0”存储信息，这些信息被编码在有效的小条形磁铁中，北极或南极指向上。 对于改进的数据存储设备，有各种各样的建议，包括可以以独特的顺时针或逆时针“涡旋”状态存储“1”和“0”的圆形纳米结构，以及在相反磁化的导线部分之间形成的畴壁中存储信息的设备。 传统上，已经使用均匀的外部场来研究磁化。 这个霍利奥克山学院（MHC）和马萨诸塞州大学阿默斯特分校（UMass）之间的合作项目使用最近开发的技术来研究磁状态，通过精确定位一根微小的导线并使电流通过产生磁场的导线来产生局部不均匀的圆形磁场。这项工作将涉及霍利奥克山学院的女本科生以及博士后和研究生，促进两个机构之间的频繁互动。 将为K12教师和附近的斯普林菲尔德技术社区学院制定有关磁性的课程材料，并将创建一个科学咖啡馆，让科学和技术专家在非正式环境中与公众交谈。

****Technical Abstract****This collaborative project between Mount Holyoke College and the University of Massachusetts, Amherst, explores magnetic states in ferromagnetic nanostructures by applying a local circular field generated by passing current through the tip of an atomic force microscope, as well as applying current pulses through the AFM tip or fabricated leads on the sample. These techniques will allow for separate control over the vortex and vortex core of magnetic disks, as well as manipulation of individual domain walls (DWs) in wires to investigate the physics of different types of DWs and interactions between them. Sufficiently thin ferromagnetic nanorings are predicted to have unique states that consist of pairs of 360 degrees domain walls (DWs) when switching between vortex states in an applied circular field. Understanding DWs and circular nano-structures will inform the next generation of data storage devices. This work will involve the undergraduate women at Mount Holyoke College, as well as post-docs and graduate students, fostering frequent interaction between the two institutions. Furthermore, curricular material on magnetism will be developed for established programs with K12 teachers and the nearby Springfield Technical Community College, and a local Science Café will be created, bringing experts in science and technology to speak with the general public in an informal setting.****Non-Technical Abstract****Computer hard drives presently store information in binary bits of "1" and "0" that are encoded in what are effectively little bar magnets with either the north or south pole pointing up. There are a variety of proposals for improved data storage devices, including circular nanostructures that could store the "1" and "0" in a unique clockwise or counterclockwise "vortex" state, and devices that store information in the domain walls that form between oppositely magnetized sections of a wire. Traditionally, magnetization has been studied using uniform external fields. This collaborative project between Mount Holyoke College (MHC) and the University of Massachusetts, Amherst (UMass), uses a recently developed technique to investigate magnetic states by generating a local non-uniform, circular magnetic field by precisely positioning a tiny wire and passing a current through the wire that creates the magnetic field. This work will involve the undergraduate women at Mount Holyoke College, as well as post-docs and graduate students, fostering frequent interaction between the two institutions. Curricular material on magnetism will be developed for established programs with K12 teachers and the nearby Springfield Technical Community College and a Science Café will be created, bringing experts in science and technology to speak with the general public in an informal setting.