CAREER: Self-Assembled Magnetic Nanostructures

技术：磁各向异性能(MAE)是磁性元件最重要的功能特性之一。它决定了磁化的方向性和稳定性，以及磁化反转的机制和动力学。这项工作的一个关键结果将是提高对MAE的原子尺度的理解，这可以极大地促进MAE值比目前可用的材料高一个数量级以上的纳米结构的工程设计。这位PI将运用他在合成纳米结构方法方面的长期专业知识，这些方法的精度和结构复杂性远远超出最先进的水平；从孤立的结构到二维和三维混合组装。从局部配位效应、与支持底物的电子杂交以及与网络结构中分子配体的相互作用等方面的系统研究，将显著提高我们对MAE的基本理解。将确定达到极大MAE的条件，这将有助于通过结构设计来设计MAE。探索室温下磁存储密度的极限将是这个五年计划的主要目标。研究内容包括：自组装磁性纳米结构的低温扫描隧道显微镜/光谱学，补充校园局部表征的X射线磁性二向色性实验，以及前往同步加速器设施进行磁性圆二向色性测量。非技术：结果将使极高密度磁记录介质的开发成为可能。这项工作将展示基于磁性纳米簇的自组装图案化介质，如果将其应用于磁记录，将允许前所未有的位密度超过每平方英寸80太比特。非技术性：由PI建造的低温STM实验室将允许使用最先进的纳米科学工具培训本科生和研究生。这将建立在一个迅速增长的领域继续研究和开发所需的人力基础设施，该领域被视为全球最重要的研究领域之一。长期目标是在UNL创建一个STM方法重要领域的专业知识中心。这一研究计划的某些方面的跨学科性质将促进与其他系的研究合作，特别有利于形成对本科生和研究生具有吸引力的研究氛围。这项工作的教育部分旨在长期留住UNL的物理学本科生和研究生课程的女性。它是基于PI以前在努力改善妇女在研究环境中的成功途径方面的经验。国际学生联合会将协调各项活动，促进女学生在国家一级建立联系，传播她们在物理学方面的贡献。作为这一计划的一个关键要素，PI将在UNL开发和主办，这是一个为物理学专业的本科生女性举办的会议。与联合国后勤基地领导人在教育宣传方面的新伙伴关系已经为第一年(试点)带来了资金。预计该项目将有助于吸引和留住优秀的女性物理学家，并显著提高女性在本科生和研究生项目中的比例。这项建议由材料研究部的金属和凝聚态物理项目以及化学部的无机化学、生物无机和有机金属化学(IBO)项目共同资助。

TECHNICAL: The magnetic anisotropy energy (MAE) is among the most important functional properties of magnetic elements. It determines the orientation and stability of the magnetization as well as the mechanisms and the dynamics of the magnetization reversal. A key result of this work will be an improved atomic-scale understanding of the MAE, which can greatly facilitate the engineering of nanostructures with MAE values that exceed those of currently-available materials by over an order of magnitude. The PI will implement his long-standing expertise in methods of synthesizing nanostructures with a precision and structural complexity well beyond the state-of-the-art; from isolated structures, to 2- and 3-dimensional hybrid assemblies. Our fundamental understanding of the MAE will improve significantly from the systematic study of local coordination effects, electronic hybridization with the supporting substrate, and interactions with molecular ligands in network structures. Conditions to achieve extremely large MAE will be identified, which could be useful for engineering the MAE by structural design. Exploring the limit of magnetic storage density at room temperature will be a key objective of this five year program Elements of research efforts include low-temperature scanning tunneling microscopy/spectroscopy on self-assembled magnetic nanostructures, x-ray magnetic dichroism experiments complementary to the local characterization on-campus, and travel to Synchrotron facilities for magnetic circular dichroism measurements.NON-TECHNICAL: Results will permit the development of extremely high density magnetic recording media. The work will demonstrate self-assembled patterned media based on magnetic nanoclusters, which, if applied in magnetic recording, would allow for unprecedented bit densities beyond 80 Terabit per square inch. NON-TECHNICAL: The Low Temperature STM lab built by the PI will allow for training of undergraduate and graduate students with state-of-the-art tools in nanoscience. This will build the human infrastructure needed to continue research and development in a rapidly growing field that is seen as one of the most significant areas of research worldwide. The long-term goal is to create at UNL, a center of expertise in the important field of STM methods. The interdisciplinary nature of some aspects in this research program will foster research collaborations with other departments and is particularly conducive to a research climate that is attractive for undergraduate and graduate students. The educational component of this work targets the long-term retention of women in UNL's undergraduate and graduate program in Physics. It is based on the PI's previous experience in efforts to improve avenues of success for women in research environments. The PI will coordinate activities to facilitate networking for women students at the national level, to disseminate their contribution in physics. As a key element of this program the PI will develop and host at UNL, a conference for undergraduate women in physics. A new partnership with leaders at UNL in educational outreach has already brought about funding for the first (pilot) year. It is expected that this program will help attract and retain outstanding women physicists to the department and increase the percentage of women in the undergraduate and graduate program significantly.This proposal is co-funded by Metals and Condensed Matter Physics program in the Division of Materials Research, and Inorganic, Bioinorganic and Organometallic Chemistry (IBO) program in the Chemistry Division.