DMREF/Collaborative Research: Designing Mutable Metamaterials with Photo-Adaptive Meta-Atoms

超材料是一种复杂的工程复合材料，具有传统材料无法达到的性能。它们不同寻常的能力来自于它们的结构，而不是从构成材料继承而来。光学超材料是一类允许以新的方式操纵光的材料，包括对偏振和波长的内置选择性，这可以允许或禁止光的传播，并有效地掩盖材料。这些材料在许多领域都有潜在的应用，包括消费电子、国防、电信和生物成像，但由于缺乏导致最佳结构和性能的合成、加工和组成的基础知识，它们的发展一直受到限制。这项旨在革新和设计我们的未来的设计材料奖(DMREF)支持通过对加工-纳米结构-性能关系的基本了解来设计和开发活性纳米超材料的研究。这种方法将使能够使用被称为超原子的可调构建块来操纵光的材料的设计成为可能，这种构建块与多波长的光相互作用。这项研究与一项推广计划紧密结合在一起，该计划包括侧重于增加STEM中代表性不足的少数族裔的参与的教育活动，以及刺激从K-12到研究生水平的教育倡议。这项研究旨在解决为活跃的光学超材料提供动力的根本挑战，特别是在纳米尺度上耦合光化能量和直接机械适应的能力，元原子逐个元原子。PI将测试这一假设，即优化驻留在光活性纳米结构聚合物上的等离子体结构的拓扑结构可以允许来自泵浦光束的光子耦合到嵌入有序大分子网络的光致变色开关。当共振模式与光开关的吸收一致时，大分子顺序的完全可逆变化可以在聚合物中产生大应变(10%)。反过来，这种激励作用会反向耦合到驻留在聚合物上的元原子的结构适应中。利用泵浦对超材料进行结构调制的能力，然后成为操纵不同波长的探测光束的工具(利用这种超原子是多共振的)，散射幅度和相位控制几乎一致。能够进行器件级光学操作的光自适应超材料成为可能。计划开展一系列外联工作，以扩大这项工作的更广泛影响。通过出版物的传播将得到加强，重点是模拟软件的开源分发和制造和处理的在线教程。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。

Metamaterials are intricately engineered composites, with properties beyond what can be achieved with conventional materials. Their unusual abilities are derived from their structure, rather than being inherited from the constituent materials. Optical metamaterials are a class of materials that allow manipulation of light in new ways, including built-in selectivity to polarization and wavelength, which can permit or forbid propagation of light and effectively mask the material. These materials have potential application across a number of sectors, including consumer electronics, defense, telecommunication and bioimaging, but their development has been limited by a lack of fundamental knowledge of the synthesis, processing, and compositions that will lead to optimal structure and performance. This Designing Materials to Revolutionize and Engineer our Future (DMREF) award supports research to design and develop active nano-scale metamaterials through fundamental understanding of the processing-nanostructure-property relationships. The approach will enable the design of materials able to manipulate light using tunable building blocks, called meta-atoms, that interact with light at multiple wavelengths. The research is tightly integrated with an outreach plan that includes educational activities focused increasing the participation of underrepresented minorities in STEM, as well as stimulating education initiatives from K-12 to the graduate student level.This research seeks to solve a fundamental challenge in powering active optical metamaterials, in particular the ability to couple actinic energy and direct mechanical adaptation at the nano-scale, meta-atom by meta-atom. The PIs will test that hypothesis that optimizing the topology of plasmonic structures which reside on photoactive, nanostructured polymers can allow coupling of photons from a pump beam into photochromic switches embedded in an ordered macromolecular network. When a resonant mode coincides with the absorption of the photoswitches, fully reversible changes in the macromolecular order can generate large strains (10%) in the polymer. In turn, this actuation back-couples into a structural adaptation of the meta-atom resident on the polymer. The ability to utilize a pump to structurally modulate a metamaterial then becomes a vehicle to manipulate a probe beam of a different wavelength (with which the meta-atoms are multiresonant) with near-unity changes in the scattering amplitude and with phase control. Photo-adaptive metamaterials capable of device-level optical manipulation become possible. An array of outreach efforts is planned to magnify the broader impact of the work. Dissemination via publications will be augmented with a focus on open-source distribution of the simulation software and online tutorials on fabrication and processing.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.