Design, Self-Assembly and Characterization of Three-Dimensional Metamaterials in the Infrared Region

非技术描述：微米和纳米结构的超材料在所有三个维度上都具有周期性图案，可以实现自然材料无法获得的新的光学性能。然而，这些超材料在微米尺度上的制造是非常具有挑战性的，这是设计红外区域光学性能所需的。该项目涉及三维材料的设计、组装和表征，这些材料由大小为0.1至10微米的周期单元组成，具有多面体几何形状和精确的图案表面。这些超材料被设计成在中红外区域显示各种以前未实现的特性，在环境监测、传感和生物医学工程方面具有潜在的应用。研究成果被整合到约翰·霍普金斯大学的红外、微和纳米技术等教育课程中。通过一系列教育活动，该项目吸收了来自巴尔的摩当地社区的K-12学生和本科生的研究经验和参与。技术描述：该项目旨在通过具有多面体几何形状的微型自折叠单元的自组装来设计和表征3D红外超材料。这项研究包括发展新的概念，如“光子金属晶格”，它结合了超材料和光子晶体的吸引人的特点，以及可重新配置的超材料。后者探索的是具有化学诱导的金属-绝缘体转变的超材料。实验方法包括最先进的纳米和微米级光刻图案、折纸灵感和聚合三维自组装。此外，还利用光学、电子显微镜和光谱学对其进行了表征，以研究其结构和光学性质。同时，在最近发展的耦合模法的基础上进行了理论研究，并用数值方法对实验结果进行了模拟。

Nontechnical Description: The micro- and nano-structured metamaterials with periodic patterns in all three dimensions can enable novel optical properties that are not attainable in naturally occurring materials. However, these metamaterials are very challenging to fabricate at micrometer length scales required to engineer the optical properties in the infrared region. This project involves the design, assembly and characterization of three-dimensional materials composed of periodic units of 0.1 to 10 micrometer in size with polyhedral geometries and precisely patterned surfaces. These metamaterials are designed to display a variety of previously unrealized properties in the mid-infrared region with potential applications for environmental monitoring, sensing, and biomedical engineering. The research results are integrated into educational curricula such as Infrared, Micro and Nanotechnologies at Johns Hopkins University. Through a number of educational activities, the project incorporates research experiences and participation of K-12 students and undergraduates including those from under-represented groups in the local Baltimore community.Technical Description: This project aims to design and characterize 3D infrared metamaterials by the self-assembly of microsized self-folded units with polyhedral geometries. The research includes the development of novel concepts such as "photonic metalattices," which combine the attractive features of metamaterials and photonic crystals, and reconfigurable metamaterials. The latter explores metamaterials that feature a chemically induced metal-insulator transition. Experimental methods include state-of-the-art nano- and micro-scale lithographic patterning, origami inspired and aggregative three-dimensional self-assembly. Furthermore, characterization using optical and electron microscopy and spectroscopy is carried out in order to investigate structural and optical properties. Simultaneously, theoretical research, based on the recently developed coupled mode methods is performed, and augmented by numerical methods to model experimental results.