3D Volumetric Reconfigurable Active Metamaterials (VRaMM)

塑造和引导电磁场的能力为工程和科学研究提供了一个重要的领域。在成像方面，它可以用于增强和聚焦领域，例如在医学成像或国土安全方面。在无线系统中，例如无线电力传输，它可以用来提高效率，保护人类和免受外来物体的干扰。在通信中，它可以用来调制、控制、限制或以其他方式操纵携带无线电信号的数据的传播。为了实现这一点，科学家们经常依赖于具有所需的电学性能(介电常数)和磁学性能(磁导率)的天然材料来塑造所需的场。不幸的是，这限制了现有材料对场整形的可用选择和应用。人工设计具有目标介电常数和磁导率的材料的能力为撞击和可以进行的科学研究提供了重要的维度。这项研究将调查一类新的人工材料，称为活性超材料。活性超材料具有介电常数和磁导率等宏观性质，可以通过设计微尺度的电子电路和结构来实现。从历史上看，这些都是被动的，包括亏损和不受欢迎的运营模式。这项研究将探索设计和开发活性超材料的新概念，这些材料将能够消除或减少损失和不需要的操作模式。过去对活性超材料研究的尝试在稳定性、可调性和规模方面面临着重大问题。目前还没有大规模、稳定的、在微波领域具有增益的活性超材料被证明。本研究将探讨提供增益补偿、稳定性及可伸缩性至100-1000微米单元的电路与结构，以实现宏规模、活性及可重构的人工材料。PI将利用教育工作坊继续向社会介绍微波工程，并在未来的工作坊中整合超材料和电磁学的想法。PI计划让本科生研究人员与研究生研究人员在拟议的项目中共同工作。PI的外展工作还包括为当地小学提供数学和机器人方面的客座讲座，并与国家科学博物馆(富兰克林研究所、卡内基科学博物馆等)接触，向从小学到高中的所有级别的学生演示工程和科学概念。在这项研究中，提出了基于主动超材料元素的3D体积可重构超材料的设计和开发，该超材料使用主动协作来稳定、编程和重新配置新的电磁材料。这些材料将是完全可编程的，并能够实现变换电磁学设想的高级应用所需的各种不均匀和各向异性特性。这些新材料将通过新的研究来实现，这些新材料将通过解决自我和细胞间耦合、大规模系统的稳定性以及通过主动取消来缓解不需要的寄生模式等主要挑战而实现。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The ability to shape and direct electromagnetic fields provides an important area of investigation in engineering and science. In imaging, it can be used to enhance and focus fields, for example in medical imaging or homeland security. In wireless systems, such as wireless power transfer, it can be used to enhance efficiency, protect humans and interference from foreign objects. In communication it can be used to modulate, steer, confine and otherwise manipulate the propagation of data carrying radio signals. To achieve this, scientists have often relied on natural materials with the desired electrical properties (permittivity) and magnetic properties (permeability) needed to shape the fields as desired. Unfortunately, this limits the available options and applications for field shaping to existing materials. The ability to artificially engineer a material with targeted permittivity and permeability provides an important dimension to the impact and scientific investigations that can be undertaken.This research will investigate a new class of artificial materials called active metamaterials. Active metamaterials have macroscale properties, such as permittivity and permeability, that can be engineered through the design of microscale electronic circuits and structures. Historically these have been passive, which include loss and unwanted modes of operation. This research will investigate new concepts to design and develop active metamaterials, that will be able to remove or mitigate loss and unwanted modes of operation. Past attempts on active metamaterial research faced significant problems with stability, tunability and scale. A large scale and stable active metamaterial with gain in the microwave domain has not yet been demonstrated. This research will investigate circuits and structures for providing gain compensation, stability, and scalability to 100-1000 of microscale cells in order to realize a macroscale, active and reconfigurable artificial material.The PI will use educational workshops to continue to introduce microwave engineering to the community and integrate the ideas of metamaterials and electromagnetics in future workshops. The PI plans to involve undergraduate student researchers to work alongside with graduate student researchers on the proposed project. The PI’s outreach efforts also include guest lectures on mathematics and robotics to local elementary schools and engagement with national science museums (Franklin Institute, Carnegie Science Museum, etc.), demonstrating engineering and science concepts to students at all levels, from elementary to high school.In this research the design and development of 3D volumetric reconfigurable metamaterials are proposed which are based on active metamaterial elements which uses active collaboration to stabilize, program and reconfigure new electromagnetic materials. These materials will be fully programable and able to achieve diverse inhomogeneous and anisotropic properties needed for advanced applications envisioned by transformational electromagnetics. These new materials will be realized through new research in solving the major challenges of self- and inter-cell coupling, stability of large-scale systems and mitigation of unwanted parasitic modes through active cancellation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.