Template-based Fabrication of Three-Dimensional Optical Metamaterials

超材料是由工程亚波长结构组成的人工介质，这使得它们具有在自然界中通常找不到的迷人的新电磁特性。它们可以用作高性能天线、完美吸收器、超级透镜、隐形装置等。与底层结构相关的响应波长是大小、形状、组成和晶格排列的函数。虽然在过去的十年中，在将超材料的响应从微波频率区转移到光学频率区方面取得了很大的进展，但在“超材料”成为光学应用的实际材料之前，仍有许多挑战需要克服。该奖项将重点研究构建三维光学超材料的廉价、易获取和大规模制造工艺。这个项目的发现将通过出版物向技术和一般读者传播，并纳入课堂教学。该项目将包括强大和持续的教育项目，涉及不同种族的本科生和地区K-12学生。将掠角沉积与二维自组装相结合，制备出一种超材料结构。三维超材料，特别是手性超材料的新设计和制造，将在数值和实验两方面进行探索。该研究团队将利用高性能电磁建模和先进的纳米制造和表征方法来创建和优化光学超材料的新型纳米结构。设计独特的光学超材料，如垂直排列的分裂环阵列、瑞士卷阵列、单螺旋/双螺旋阵列等，并确定其制造条件。预计这些结构在近红外和可见区表现出负折射率性质，螺旋结构在近红外和可见区表现出强的电磁手性。这些结构在电磁隐身、反隐身和超级透镜中的应用将从理论上和实验上进行探索。

Metamaterials are artificial media composed of engineered sub-wavelength structures, which cause them to have fascinating new electromagnetic properties that are not usually found in nature. They could be used as high performance antennae, perfect absorbers, super-lenses, cloaking devices, etc. The response wavelengths associated with the underlying structures are a function of size, shape, composition and lattice arrangement. Although there has been great progress in shifting the response of metamaterials from the microwave frequency regime to the optical frequency regime over the past 10 years, there are still many challenges to overcome before "metamaterials" become practical materials for optical applications. This award will focus on studying an inexpensive, accessible, and large-scale fabrication process to construct three-dimensional optical metamaterials. Discoveries from this project will be disseminated to technical as well as general audiences through publications, and incorporated into classroom teaching. The project will include strong and sustained education programs involving both undergraduate students with diverse ethnicity and regional K-12 students. A metamaterial structure will be fabricated through the combination of glancing angle deposition and two-dimensional self-assembly methods. Novel design and fabrication of three-dimensional metamaterials, especially chiral metamaterials, will be explored both numerically and experimentally. The research team will take advantage of both high-performance electromagnetic modeling and advanced nanofabrication and characterization methods to create and optimize novel nano-architectures for optical metamaterials. Unique optical metamaterials, such as vertically aligned split ring arrays, Swiss roll arrays, and single helical/double helical arrays, etc., will be designed and their fabrication conditions will be determined. It is expected that these structures will demonstrate negative index properties in the near infrared and visible region of the electromagnetic spectrum, and that helical structures will exhibit strong electromagnetic chirality in the near infrared-visible region. The use of these structures in electromagnetic cloaking, anti-cloaking, and super-lenses will be explored both theoretically and experimentally.