Nonlinear Spin Waves in Magnetic Films: New Concepts and Applications

磁性薄膜中的非线性自旋波：新概念和应用

• 批准号: 0906489
• 负责人: Mingzhong Wu
• 金额: $ 33万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0906489&HistoricalAwards=false
• 关键词: Nonlinear; Spin; Waves; Magnetic; Films

****NON-TECHNICAL ABSTRACT**** Chaos and solitons are two important branches of nonlinear science that have attracted interest over a wide range of disciplines, including mathematics, physics, biology, and engineering. Chaos is the idea that outcomes are highly sensitive to initial conditions: a butterfly flaps its wings in New York and there is a storm in Tokyo. Solitons are localized waves like tsunamis, and frequently occur in weakly nonlinear systems. Usually one believes that chaos and solitons are opposed to each other ? a soliton can be strongly perturbed and yet persists, for example, making it difficult to stop, say, a tsunami. This project will seek connections between chaos and solitons. Specifically, the project will take advantage of spin waves (a travelling disturbance in the magnetic order) in magnetic film systems to explore these connections. On the applied side, the project will develop a new secure communication scheme that exploits the solitons in feedback rings. This is a joint program between one experimental group and one theoretical group in two universities. Through the training of students in both experimental and theoretical nonlinear dynamical methods, the project will help young scientists cross the divide between ?theory land? and physical reality, leading to both better experiments and better theories. The education portion also includes the incorporation of nonlinear dynamics and chaos into undergraduate and graduate curricula and reaching out to students in disadvantaged high schools in Colorado.****TECHNICAL ABSTRACT****This project will take advantage of spin waves in magnetic film systems to explore a possible crossover between solitons and chaos. The project will explore ?chaotic carrier solitons? ? solitons with chaotic carrier waves. A magneto-dynamic probe will be used to study the evolution of a pulse of chaotic spin waves and the formation of an envelope soliton from such a pulse. The project will also explore ?chaotic solitons? ? solitons that have coherent carrier waves but exhibit chaotic behaviors in time. The work will include the study of chaotic soliton excitation through modulational instability and chaotic solitons in magnetic film feedback rings. On the applied side, the project will develop a new secure communication scheme that exploits the soliton-associated Fermi-Pasta-Ulam recurrence in feedback rings. For all the projects, theoretical modeling will inspire, support, and interpret experimental work. The education portion focuses on the incorporation of nonlinear dynamics and chaos into undergraduate and graduate curricula both through core courses and through the design of new electives, as well as training of undergraduate and graduate researchers and reaching out to students in disadvantaged high schools.

****非技术抽象****混乱和孤子是非线性科学的两个重要分支，在包括数学，物理，生物学和工程学在内的广泛学科中引起了兴趣。 混乱是结果对初始条件高度敏感的想法：蝴蝶在纽约的翅膀拍打，在东京有一场风暴。 孤子是诸如海啸之类的局部波，并且经常发生在弱非线性系统中。 通常人们认为混乱和孤儿彼此反对吗？孤儿可能会受到强烈的扰动，但仍然存在，例如，很难停下来，例如海啸。 该项目将寻求混乱与孤儿之间的联系。 具体而言，该项目将利用磁性膜系统中的自旋波（在磁性顺序中的行进干扰）来探索这些连接。 在应用方面，该项目将开发一种新的安全通信方案，以在反馈环中利用孤子。 这是两个大学中一个实验组和一个理论组之间的联合计划。通过对实验和理论非线性动力学方法的学生培训，该项目将帮助年轻的科学家跨越“理论土地”之间的鸿沟？和物理现实，导致更好的实验和更好的理论。 教育部分还包括将非线性动力和混乱纳入本科和研究生课程，并与科罗拉多州处境不利的高中的学生接触。****技术摘要****该项目将利用磁性电影中的旋转波探索孤子和混乱之间可能的交叉的系统。 该项目将探索混乱的载体孤子吗？ ？带有混沌载波的孤子。 磁动力探针将用于研究混沌自旋波的脉冲的演变，并从这种脉冲中形成孤子。 该项目还将探索混乱的孤子吗？ ？具有连贯的载波但及时表现出混沌行为的孤子。 这项工作将包括通过模量不稳定性和磁性膜反馈环中的混沌孤子来研究混乱的单人激发。 在应用方面，该项目将开发一种新的安全通信方案，以利用反馈环中与孤子相关的费米 - 帕斯塔 - 乌拉姆复发。 对于所有项目，理论建模将激发，支持和解释实验工作。 教育部分着重于通过核心课程以及新的选修课的设计以及对本科和研究生研究人员的培训，并与缺席的高中的学生接触，将非线性动态和混乱纳入本科和研究生课程。