EAPSI: Detection and Manipulation of the Exotic Magnetic Structures known as Skyrmions in Nanowires for Next Generation Information Storage Applications

高密度信息存储系统的改进，如磁性硬盘驱动器，对于计算机和互联网的持续成功至关重要。与计算机处理器（CPU）仍有相当大的传统改进空间不同，信息存储系统（如磁性硬盘驱动器）正在接近其极限，需要新材料来突破这些极限。一种在物理学界引起广泛关注的新方法是使用被称为skyrmions的奇异磁畴，它类似于磁泡，可以写入和存储信息。这些吗？磁泡？可以小于当前在磁性硬盘驱动器中使用的磁畴，其可以允许在更小的区域中存储更多的信息。PI将与中国科学院的田明莲教授合作，田教授是电子应用纳米磁性领域的知名专家，包括skyrmions。沿着田的专业知识，他的实验室有一些仪器，允许skyrmions及其在单纳米线器件原型中的电子应用的研究。FeGe和Mn 1-xFexSi的新型纳米线已知的主机skyrmions已经通过化学气相沉积路线合成。每种类型的纳米线的单纳米线器件将在田教授？的实验室使用他们的最先进的聚焦离子束（FIB）。FIB将Pt电引线写入由显微操作器拾取的隔离线。然后将使用小组中进行的磁电阻和霍尔效应测量来绘制纳米线中skyrmion相的稳定性？物理性能测量系统（PPMS）。与大单晶相比，由于skyrmions在纳米线宿主中的空间限制，skyrmions的稳定性预计会增加。一旦绘制出每个系统的Skyrmion相图，将研究新的电学检测方法。如果该项目成功，两个新的纳米线系统将彻底研究它们的skyrmion属性，更重要的是，将开发一种新颖而简便的方法来检测单个skyrmion。能够检测单个Skyrmion将是在下一代电子信息存储系统中利用Skyrmion的一大步。 该奖项属于东亚和太平洋夏季研究所计划，支持美国研究生的夏季研究，由NSF和中国科技部共同资助。

Improvement of high density information storage systems, such as magnetic hard drives, is imperative for the continued success of computers and the internet. Unlike computer processing units (CPUs) which still have a fair amount of room for traditional improvement, information storage systems, like magnetic hard drives, are approaching their limits and will need new materials to break through these limits. One new approach that has garnered much attention in the physics community is the use of exotic magnetic domains known as skyrmions which are analogous to magnetic bubbles in which information can be written and stored. These ?magnetic bubbles? can be smaller than the magnetic domains used currently in magnetic hard drives which can allow for more information to be stored in a smaller area. The PI will collaborate with Professor Minglian Tian at the Chinese Academy of Sciences who is a known expert in the field of nanoscale magnetism for electronics applications which includes skyrmions. Along with Tian's expertise, his lab has a number of instruments that allow for the study of skyrmions and their electronic applications in single nanowire device prototypes.Novel nanowires of FeGe and Mn1-xFexSi which are known to host skyrmions have been synthesized via a chemical vapor deposition route. Single nanowire devices of each type of nanowire will be made in Prof. Tian?s lab using their state of the art Focus Ion beam (FIB). The FIB will write Pt electrical leads to an isolated wire picked by a micromanipulator. The stability of the skyrmion phase in the nanowires will then be mapped using magnetoresistance and Hall effect measurements carried out in the group?s own physical properties measurement system (PPMS). The stability of the skyrmions is expected to be increased compared to large single crystals due the spatial confinement of the skyrmions in the nanowire host. Once the skyrmion phase diagram has been mapped for each system, new electrical detection methods will be studied. If the project is successful, two new nanowire systems will have had their skyrmion properties thoroughly studied, and more importantly a novel and facile way to detect single skyrmions will be developed. Being able to detect single skyrmions would be a large step toward utilizing skyrmions in next generation electronic information storage systems. This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Ministry of Science and Technology of China.