Novel Capabilities and Devices Using Plasmonic Lattices in Conventional and Exotic Metals

摘要目的：提出的研究目标是阐明这种现象的潜在特性，并利用这些知识开发独特而有用的太赫兹光谱范围的器件能力。智力优势：在过去的十年中，人们对等离子体动力学领域的兴趣急剧增加，因为可以探索引人注目的新物理学，以及与许多发现的现象相关的新的独特应用的潜力。有一个特别的现象引起了极大的注意，那就是通过亚波长孔径阵列（也称为等离子体晶格）增强的光传输。在研究计划期间，我们将使用时域光谱学来研究太赫兹频率下等离子体晶格的传输特性，与现有的光学频率研究相比，时域光谱学具有几个独特的优势：(i)与光学频率不同，只有金和银能够支持表面等离子体极化子的相对低损耗传播，广泛的金属包括铝，不锈钢，以及更多的外来金属，如重掺杂导电聚合物和金属单壁碳纳米管；在太赫兹频率下工作良好（ii）太赫兹频率下的传输共振比光学频率下的类似共振表现出更高的质量因子（iii）太赫兹时域光谱允许直接测量通过结构传输的太赫兹电场，产生幅度和相位信息。更广泛的影响：潜在的应用包括生物医学和国土安全应用的传感、短程自由空间通信和成像。拟议的研究具有很强的跨学科性质，将有助于培养来自多个系的研究生和本科生，他们将参与研究项目的各个方面。

Abstract Objective: The goal of the proposed research is to elucidate the underlying properties of the phenomenon, and use this knowledge to develop unique and useful device capabilities for the THz spectral range. Intellectual Merit:Over the last decade, interest in the field Plasmonics has increased dramatically, because of the striking new physics that can be explored and the potential for new and unique applications associated with many of the discovered phenomena. One particular phenomenon that has elicited significant attention is that of enhanced optical transmission through arrays of subwavelength apertures (also known as plasmonic lattices). During the research program period, we will examine the transmission properties of plasmonic lattices at THz frequencies using time-domain spectroscopy, which offers several unique advantages over existing studies performed at optical frequencies: (i) Unlike at optical frequencies, where only gold and silver are able to support relatively low loss propagation of surface plasmon-polaritons, a broad range of metals including aluminum, stainless steel, as well as more exotic metals such as heavily doped conducting polymers and metallic single walled carbon nanotubes, work well at THz frequencies (ii) the transmission resonances at THz frequencies exhibit a higher quality factor than similar resonances at optical frequencies (iii) THz time-domain spectroscopy allows for a direct measurement of the THz electric field transmitted through the structures, yielding both amplitude and phase information. Broader Impact:Potential applications include sensing for biomedical and homeland security applications, short range free-space communications, and imaging. The strong interdisciplinary nature of the proposed research will serve to educate graduate and undergraduate students from multiple departments, who will be involved in all aspects of the research projects.