Electrical control of nontrivial textures in magnetic nanostructures

非技术描述：对具有新功能的更小、更快设备的技术需求推动了对物质的非平凡状态的科学探索，这些状态在缩小到只有几纳米时保持稳定。该项目研究的是Skyrmions--一种非平凡的纳米级磁性结构，它不会被磁化的持续演化所湮灭。这种纹理可以小到几个纳米，这使得用传统的显微镜技术研究它们变得困难，因此人们对它们的性质或如何用于纳米设备知之甚少。该项目使用纳米结构中的磁电子测量来获得相关的长度销售，并研究使用局部注入到超薄磁性薄膜中的电流来创建、操纵和探测Skyrmions的可能性。这项研究与本科生和研究生的培训相结合，为亚特兰大地区蓬勃发展的更广泛的纳米科学研究、教育和推广工作做出了贡献。技术描述：该项目研究磁性材料中的磁性天子--在拓扑上不是平凡的状态，这种状态不能通过连续转换“微不足道”的状态获得，因此显示出更高的稳定性、异常的动力学特性和对扰动的响应。这项研究利用基于垂直各向异性超薄磁性薄膜的纳米块状磁性纳米结构，以及磁电子技术来产生、表征和操纵电流作用下的天空粒子的静态和动态。材料科学和磁性工程被用来实现显著的Dzyaloshinskii-Moriya相互作用，能够在没有电流的情况下稳定Skyrmions。新的测量方法，如三端霍尔效应，是专门为研究纳米尺度上的现象而设计的，这些现象是现有技术无法实现的。这项研究对拓扑织构对材料性质的影响提供了基本的见解，并为它们的实验探索以及在纳米级磁电子(自旋电子器件)中的可能应用开辟了道路。除了直接培训两名研究生外，该项目的影响还大大增强，因为它在支持国际和平研究所向埃默里大学和更大范围的亚特兰大地区的研究人员提供免费共享的凝聚态和纳米科学研究设施方面发挥了作用，本科生和高中生参与了研究，并为亚特兰大科学节和小学科学日等大型特别活动做出了贡献。

Nontechnical description: The technological demand for smaller and faster devices capable of new functionalities drives the scientific exploration of the nontrivial states of matter that remain stable when scaled down to just a few nanometers. The Project studies the skyrmions - nontrivial nanoscale magnetic textures that cannot by annihilated by a continuous evolution of magnetization. Such textures can be as small as a few nanometers, making it difficult to study them by the conventional microscopy techniques, and consequently very little is known about their properties or how they can be used in nanodevices. The Project uses magnetoelectronic measurements in nanofabricated structures to access the relevant length sales, and investigate the possibility to use electrical current locally injected into ultrathin magnetic films to create, manipulate, and detect skyrmions. The research is integrated with the training for undergraduate and graduate students, and contributes to the burgeoning broader nanoscience research, education and outreach efforts in the Atlanta area.Technical description: The Project investigates magnetic skyrmions - topologically nontrivial states in magnetic materials, which cannot be obtained by a continuous transformation of "trivial" states, and thus exhibit higher stability, unusual dynamical characteristics and response to perturbations. The research utilizes nanofabricated magnetic nanostructures based on ultrathin magnetic films with perpendicular anisotropy, and magnetoelectronic techniques to generate, characterize, and manipulate both static and dynamical states of skyrmions by electrical current. Materials science and magnetic engineering are used to achieve a significant Dzyaloshinskii-Moriya interaction capable of stabilizing skyrmions in the absence of current. New measurement approaches, such as three-terminal Hall effect , are designed specifically to investigate phenomena on nanoscale not accessible with the established techniques. This research provides fundamental insight into the effects of topological textures on the material properties, and develops routes for their experimental exploration as well as possible applications in nanoscale magnetoelectronic (spintronic) devices. In addition to directly training two graduate students, the impact of the Project is significantly enhanced by its role in supporting the free shared condensed matter and nanoscience research facilities provided by the PI to researchers at Emory University and in the larger Atlanta area, research involvement of undergraduates and high school students, and contribution the large special events such as the Atlanta Science Festival and the Elementary School Science Day.