Controlling Multiple Domain Walls in Ferromagnetic Nanowires with Magnetic Fields Studies by Micromagnetic Simulation

通过微磁模拟研究磁场控制铁磁纳米线中的多个畴壁

• 批准号: 1006947
• 负责人: Andrew Kunz
• 金额: $ 11.4万
• 依托单位: Marquette University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-15 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1006947&HistoricalAwards=false
• 关键词: Controlling; Multiple; Domain; Walls; Ferromagnetic

TECHNICAL SUMMARYThis award supports computational and theoretical research on magnetization dynamics in magnetic nanostructures that is integrated with undergraduate student education.This project aims to advance the understanding of the interaction between the magnetic state and the surface of nanoscale structures, in particular, the dependence of domain wall positioning due to defects and other domain walls inside the material. Many magnetic devices for recording, sensing, and logic operations have been proposed in which the motion and control of a domain wall in a nanowire is a necessary operating condition. Most of these proposed devices require the control of individual domain walls in the presence of others within the same structure which necessitates the need for understanding the important interactions taking place.The project will engage undergraduate physics majors to participate in carrying out computer simulations. Students will benefit from the research experience, and in the process, add to their education in magnetic materials and nanotechnology.New theories and computer simulations will be employed to understand and predict the behavior for control of the multiple magnetic domains that exist in nanowires. This work employs micromagnetic simulation methods to help test and validate theories and aid in the interpretation of experiments on motion of the magnetic domains. The combination of nanometer spatial resolution with concurrent picosecond temporal resolution makes micromagnetic simulation an ideal method for studying the field driven domain wall motion in a magnetic nanowire. Dynamic observation of domain wall motion in a magnetic nanowire is difficult experimentally due to the small size of nanowires. Investigations will yield techniques to manipulate individual domain walls in the presence of other walls without the loss of critical information. Ultimately this work impacts the viability of the proposed devices and increases the base of knowledge about magnetization dynamics in nanostructured materials as opposed to bulk materials.NONTECHNICAL SUMMARYThis award supports computational and theoretical research that is well integrated with undergraduate student education. In this initiative research and education are developed to advance the theory of and the use of computers to simulate magnetic materials for nanoscale recording devices. Research efforts concentrate on understanding and advancing the manipulation of magnetic materials in nanostructures that are needed to understand and control magnetic devices and to promote their future use in high density and extremely fast magnetic recording devices.The project engages undergraduate physics majors to participate in carrying out the computer simulation and theoretical modeling. Students benefit from the research experience which in the process adds to their education in magnetic materials and nanotechnology. Some of the simpler interpretations and results are used for current topics in introductory courses to highlight the importance of classical physics in modern research and technology.New theories and computer simulations are employed to understand and reliably control the individual magnetic regions that can be created in nanodevices. The motion of these regions is being investigated by experiments and theories because of the potential application in extremely fast and small magnetic storage and sensing applications. This project employs computer simulation methods to help test and validate theories and aid in the interpretation of experiments on motion of the magnetic regions. Computer simulation is the only technique which gives simultaneous access to space and time in such small structures.The results of the proposed simulations are also important to understanding how to manipulate the location of a particular magnetic region in the nanowire which is then the basis for switching and logic. Reliable control of the magnetic region location and motion in magnetic nanodevices is essential to future generations of magnetic hard drives, as well as the logic devices. Manipulating the motion could lead to the creation of variable magnetic field sensors which depend on the magnetic domain location or number of domains.

该奖项支持与本科生教育相结合的磁性纳米结构中磁化动力学的计算和理论研究。该项目旨在推进对磁性状态与纳米结构表面之间相互作用的理解，特别是由于材料内部缺陷和其他畴壁导致的畴壁定位的依赖性。 已经提出了许多用于记录、感测和逻辑操作的磁性器件，其中纳米线中的畴壁的运动和控制是必要的操作条件。 大多数这些提议的设备需要在同一结构中的其他设备存在的情况下控制单独的畴壁，这需要理解发生的重要相互作用。该项目将吸引物理专业的本科生参与进行计算机模拟。学生将从研究经验中受益，并在此过程中，增加他们在磁性材料和纳米技术方面的教育。新的理论和计算机模拟将被用来理解和预测存在于纳米线中的多个磁畴的控制行为。 这项工作采用微磁模拟方法来帮助测试和验证理论，并帮助解释磁畴运动的实验。 微磁学模拟结合了纳米级的空间分辨率和皮秒级的时间分辨率，成为研究磁性纳米线中场驱动畴壁运动的理想方法。由于纳米线的尺寸很小，在实验上很难动态观察磁性纳米线中畴壁的运动。 调查将产生技术来操纵个别域墙在其他墙的存在，而不会丢失的关键信息。 最终这项工作的可行性的影响，提出的设备，并增加了基础知识的磁化动力学纳米结构材料，而不是散装material.NONTECHNICAL总结这个奖项支持计算和理论研究，是很好地结合了本科生教育。在这项倡议中，研究和教育的发展，以推进理论和使用计算机来模拟纳米级记录设备的磁性材料。研究工作集中在理解和推进纳米结构中的磁性材料的操纵，这是理解和控制磁性器件所需的，并促进其在高密度和极快速磁记录器件中的未来应用。该项目邀请物理专业的本科生参与进行计算机模拟和理论建模。学生受益于研究经验，在此过程中增加了他们在磁性材料和纳米技术的教育。 一些简单的解释和结果被用于当前的主题，在入门课程，以强调经典物理学在现代研究和技术的重要性。新的理论和计算机模拟被用来理解和可靠地控制可以在纳米器件中创建的单个磁性区域。这些区域的运动正在通过实验和理论进行研究，因为它们在极快速和小型磁存储和传感应用中具有潜在的应用。这个项目采用计算机模拟方法来帮助测试和验证理论，并帮助解释磁性区域运动的实验。 计算机模拟是唯一的技术，使同时访问空间和时间在这样的小结构，所提出的模拟的结果也是重要的理解如何操纵的纳米线中的一个特定的磁性区域的位置，然后是开关和逻辑的基础。磁性纳米器件中磁性区域位置和运动的可靠控制对于未来几代磁性硬盘驱动器以及逻辑器件至关重要。操纵运动可能导致产生取决于磁畴位置或磁畴数量的可变磁场传感器。