CAREER: Magnetic Bubble Dynamics in Nanodisks with Perpendicular Magnetic Anisotropy

****非技术摘要****该奖项支持一所女子文理学院的实验纳米磁学研究，该学院有一个小型的男女合校博士项目。纳米磁学是一个特别令人兴奋的研究领域，因为它在物理学中的基础作用以及它潜在的技术应用。先进纳米技术的发展使得在纳米尺度上对材料的操纵能够实现新的功能。本文的研究方向是设计、制作和研究具有垂直磁各向异性的新型纳米磁片。这将通过采用最先进的实验科学工具来完成：纳米制造，高分辨率磁成像，具有高时空分辨率的时间分辨同步加速器x射线成像，以及微磁模拟。本研究将提供对纳米磁体自旋动力学的新认识，揭示纳米磁学的各种基本物理问题，并拓宽纳米磁体动力学实验的范围。该项目还将为本科生和研究生提供深入的研究经验和支持性指导。此外，该项目将开发一个跨学科的纳米科学课程和一个互动网站，向公众宣传年轻女科学家的成就。****技术摘要****该奖项支持一所女子文理学院的实验纳米磁学研究，该学院有一个小型的男女合校博士项目。本文主要研究垂直磁各向异性（PMA）纳米片的磁泡动力学。磁泡状态是一种稳定的双畴结构，存在于具有PMA的纳米磁盘中，它由一个圆形畴壁组成，该畴壁将纳米磁盘分隔成两个相反的面外磁化磁畴。磁泡中的非平凡拓扑结构有望产生新的自旋动力学，具有潜在的新技术应用。为了探测磁泡动力学，将使用时间分辨率为90 ps、空间分辨率为100 nm的时间分辨光电发射电子显微镜（TR-PEEM）。研究了基态磁泡的独特运动及其基态和激发态之间的转换。此外，还将探讨激发态下的非线性自旋动力学和电流诱导的自旋动力学，以开发基于磁泡的自旋电子器件。该项目还将为本科生和研究生提供深入的研究经验和支持性指导。此外，该项目将开发一个跨学科的纳米科学课程和一个互动网站，向公众宣传年轻女科学家的成就。

****NON-TECHNICAL ABSTRACT****This award supports experimental nanomagnetism research at a women's liberal arts college with a small co-educational Ph.D. program. Nanomagnetism is a particularly exciting area of research due to its fundamental role in physics as well as its potential technological applications. The development of advanced nanotechnology enables the manipulation of materials at the nanoscale to realize new functionality. The research proposed here is to design, fabricate and study novel magnetic nanodisks with perpendicular magnetic anisotropy. This will be accomplished by employing the most advance tools of experimental science: nanofabrication, high-resolution magnetic imaging, time-resolved synchrotron x-ray imaging with high temporal and spatial resolutions, and micromagnetic simulations. This research is expected to provide a new understanding of spin dynamics in nanomagnets, shed light on a variety of fundamental physics topics in nanomagnetism, and widen the scope for dynamical experiments in nanomagnets. This project will also provide undergraduate and graduate students an in-depth research experience and supportive mentoring. In addition, the PI will develop an interdisciplinary nanoscience course and an interactive website to educate the public about the achievements of young women scientists. ****TECHNICAL ABSTRACT****This award supports experimental nanomagnetism research at a women's liberal arts college with a small co-educational Ph.D. program. The research proposed here is to study magnetic bubble dynamics in nanodisks with perpendicular magnetic anisotropy (PMA). The magnetic bubble state, a stable bi-domain configuration existing in nanodisks with PMA, consists of a circular domain wall that separates the nanodisk into two magnetic domains of opposite out-of-plane magnetizations. The nontrivial topological structure in the magnetic bubble is expected to result in novel spin dynamics with potentially new technological applications. To probe the magnetic bubble dynamics, time-resolved photoemission electron microscopy (TR-PEEM) with a 90 ps time resolution and 100 nm spatial resolution will be used. The unique motion of a ground-state magnetic bubble and the switching between the ground and excited states of the bubbles will be investigated. The non-linear spin dynamics in the excited bubble state and current-induced bubble dynamics will also be explored with the intent of developing a magnetic bubble-based spintronic device. This project will also provide undergraduate and graduate students an in-depth research experience and supportive mentoring. In addition, the PI will develop an interdisciplinary nanoscience course and an interactive website to educate the public about the achievements of young women scientists.