Collaborative Research: Spin-Torque Devices for Microwave Nano-Electronics Based on One-Dimensional Array of Magnetic Nano-Contacts

合作研究：基于一维磁纳米触点阵列的微波纳米电子自旋力矩器件本合作提案的目标是创建一个实验原型并发展一种新型纳米电子微波器件的操作理论：基于磁波导耦合的锁相磁纳米触点阵列的可调谐微波振荡器。所提出的装置将在连接铁磁自旋波波导的磁性纳米触点中利用自旋扭矩效应。该器件的工作原理是基于自旋极化直流电在自旋波波导中激发的自旋波之间的相互作用。这些器件的工作频率将由外部磁场和直接偏置电流调节，频率范围在10至25 GHz之间。提出的基于自旋波波导的新型准一维器件几何结构也将使我们能够显着增加单个纳米触点之间的耦合（与通常的二维几何结构相比），因此，增加锁相的频带并放宽对纳米触点尺寸均匀性的限制。这种一维几何结构也会增加输出功率，减小振荡器阵列的产生线宽。新的几何结构将使我们能够获得关于单个自旋-扭矩振荡器之间耦合机制的新实验信息，从而导致其锁相。智力优势：拟议的研究计划将导致开发一种新型可调谐纳米级微波振荡器，具有未来微波纳米电子学所需的独特特性组合：与硅基半导体电子学的兼容性，可扩展性降低到最终的纳米级限制，极低的功耗，以及由于缺乏半导体元件而导致的辐射硬度。本研究也将促进我们对磁性纳米结构中自旋极化电流与动态磁化之间相互作用的物理理解。我们的目标是充分利用加州大学欧文分校的实验组和密歇根州罗彻斯特奥克兰大学的理论组之间的协同作用，在微波纳米电子学的实用纳米级器件技术的发展上取得突破。更广泛的影响：拟议的研究计划将以多种方式影响我们的社会。在这个项目中开发的新型有源纳米级微波器件对于美国在电子和磁记录技术方面的持续领导地位非常重要。一些研究生和博士后将通过参与拟议的研究，接触到现代纳米科学和纳米技术的方法。该计划将通过参与手稿准备和会议演讲，帮助学生发展写作、演讲和指导技能。该项目还将通过与国内外领先研究小组的合作研究，大大提高和拓宽学生的教育经验。该计划提供的纳米制造实践培训将为美国电子和磁记录行业准备有价值的专家，这些行业目前正经历从微观到纳米尺度的快速过渡。该计划还将导致将纳米技术的理论和实验方法纳入研究生和本科大学课程。

Collaborative Research: Spin-Torque Devices for Microwave Nano-Electronics Based on One-Dimensional Array of Magnetic Nano-ContactsThe goal of this collaborative proposal is to create an experimental prototype and develop theory of operation of a new microwave device for nano-electronics: tunable microwave oscillator based on a phase-locked array of magnetic nano-contacts coupled by a magnetic waveguide. The proposed device will employ the spin-torque effect in magnetic nano-contacts connected to a ferromagnetic spin wave waveguide. The device operational principles are based on the interactions between spin waves excited in a spin wave waveguide by spin-polarized direct current. The frequency of operation of these devices will be tunable by the external magnetic field, as well as by the direct bias current, in the frequency range between 10 and 25 GHz. The proposed novel quasi-one-dimensional device geometry based on the spin wave waveguides will also allow us to dramatically increase the coupling between the individual nano-contacts (in comparison to the usual two-dimensional geometry), and, therefore, to increase the frequency band of phase-locking and relax the restrictions on the size uniformity of the nano-contacts. This one-dimensional geometry will also increase the power output and reduce the generation linewidth of the oscillator array. The new geometry will allow us to obtain new experimental information on the mechanisms of coupling between individual spin-torque oscillators leading to their phase-locking. Intellectual merit: The proposed research program will result in the development of a new class of tunable nano-sized microwave oscillators with a unique combination of properties required for future microwave nano-electronics: compatibility with silicon-based semiconductor electronics, scalability down to the ultimate nano-scale limits, extremely low power consumption, and radiation hardness due to the absence of semiconductor elements. The proposed research will also advance our understanding of the physics of interaction between spin-polarized current and dynamic magnetization in magnetic nanostructures. Our aim is to use the full benefit of synergistic interaction between the experimental group of the University of California, Irvine, California and the theoretical group of the Oakland University, Rochester, Michigan, to achieve a breakthrough in the development of practical nano-scale device technology for microwave nano-electronics. Broader impacts: The proposed research program will impact our society in multiple ways. The new types of active nano-scale microwave devices to be developed in this program are important for the continuing leadership of the USA in electronics and magnetic recording technology. A number of graduate and postdoctoral students will be exposed to the methods of modern nano-science and nano-technology through the participation in the proposed research. The proposed program will help develop writing, presentation, and mentoring skills of our students through the participation in the manuscript preparation and conference presentations. The program will also substantially enhance and broaden students' educational experience through the collaborative research with the leading foreign and domestic research groups. The practical training in nano-fabrication offered by this program will prepare valuable specialists for the US electronics and magnetic recording industries that are currently undergoing a rapid transition from micro- to nano-scale. The program will also result in incorporating theoretical and experimental methods of nano-technology into graduate and undergraduate university curricula.