Frequency Agile Devices Based on Stimuli-Active Magnetic Nanowire Composites

基于刺激活性磁性纳米线复合材料的捷变频器件

• 批准号: 1028547
• 负责人: Leonard Spinu
• 金额: $ 34.5万
• 依托单位: University of New Orleans
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1028547&HistoricalAwards=false
• 关键词: Frequency; Agile; Devices; Based; Stimuli

The objective of this research is to develop novel frequency agile reciprocal (tunable filters) and non-reciprocal (isolator and circulator) microwave devices based on stimuli-responsive magnetic nanowires composites. In the modern world when wireless connectivity guarantees to provide voice, video and data access to ?everyone, anywhere, and anytime? there is a constant need for remotely tunable microwave devices. The proposed research will integrate fabrication of magnetic nanowires, frequency agile microwave device design, characterization and modeling.Intellectual Merit. For more than half a century the ferrites were the ?workhorse? of the microwave devices, especially for nonreciprocal applications. The main advantage of ferrites is the fact that they provide an extremely high electrical resistivity with reasonable good magnetic properties, which is very important at high frequencies view the eddy?current loss. However, their average magnetic properties impacts negatively the size and weight of ferrite based microwave devices. The stimuli-responsive magnetic nanowires composites will combine the advantages provided by superior electromagnetic properties of magnetic nanowires with the ability of the active polymer matrix to provide a remote tuning of these electromagnetic properties. Piezoelectric and light active polymers will be used to couple magnetic nanowires in planar structures. In the case of a piezoelectric matrix, an electric field applied across the device?s plane will determine a variation in its planar dimensions which will change the average distance between the magnetic nanowires. For light active polymers, besides a variation of the average interwire distance, a change in the angular texture of the wires can be triggered as the planarity of the polymer film changes under the action of an optical stimulus. Both of these coupling mechanisms between magnetic nanowires and stimuli responsive matrices will affect the frequency response of the composite material, as the ferromagnetic resonance frequency is strongly dependent on interwire interactions and orientation of the wires.Broader Impact. The findings gained from this project will contribute to the basic understanding of the nanoscale physical phenomena, specifically nanomagnetism, providing insights into the dynamic properties of mesoscopic magnetic structures. The immediate benefit for the society comes from the big impact of the proposed activity on rf and microwave technologies. Also, this project will provide important training for graduate and undergraduate students in Physics, Chemistry and Nanomaterials Science. Students will be involved in all aspects of this program gaining important experience in processing and characterization of these materials. Further, this program will serve to expand nanotechnology education in Louisiana by exposing undergraduates students, especially minorities, to the latest research developments.

本研究的目的是开发基于刺激响应磁性纳米线复合材料的新型频率捷变互易（可调谐滤波器）和非互易（隔离器和循环器）微波器件。在现代世界，无线连接保证为“每个人、任何地点、任何时间”提供语音、视频和数据访问。对远程可调谐微波设备的需求一直存在。拟议的研究将整合磁性纳米线的制造、频率捷变微波器件设计、表征和建模。智力优点。半个多世纪以来，铁氧体一直是“主力”。微波器件，特别是对于不可逆应用。铁氧体的主要优点是它们具有极高的电阻率和良好的磁性能，这在高频时非常重要（考虑涡流损耗）。然而，它们的平均磁性会对基于铁氧体的微波器件的尺寸和重量产生负面影响。刺激响应磁性纳米线复合材料将磁性纳米线的优异电磁特性所提供的优点与活性聚合物基质提供远程调节这些电磁特性的能力结合起来。压电和光活性聚合物将用于耦合平面结构中的磁性纳米线。 在压电矩阵的情况下，施加在器件平面上的电场将决定其平面尺寸的变化，这将改变磁性纳米线之间的平均距离。对于光活性聚合物，除了平均线间距离的变化之外，当聚合物膜的平面度在光刺激的作用下发生变化时，可以触发线的角度纹理的变化。磁性纳米线和刺激响应基质之间的这两种耦合机制都会影响复合材料的频率响应，因为铁磁共振频率强烈依赖于线间相互作用和线的方向。更广泛的影响。 该项目获得的发现将有助于对纳米级物理现象（特别是纳米磁性）的基本理解，为介观磁性结构的动态特性提供见解。所提议的活动对射频和微波技术的巨大影响将为社会带来直接利益。此外，该项目还将为物理、化学和纳米材料科学方面的研究生和本科生提供重要的培训。 学生将参与该计划的各个方面，获得这些材料的处理和表征方面的重要经验。 此外，该计划还将通过向本科生（尤其是少数族裔）展示最新的研究进展，扩大路易斯安那州的纳米技术教育。