Electromagnetic Metamaterials for Wave Manipulation

Abstract

The overarching problem addressed in this dissertation is the restricted number of devices that operate in the millimeter wave, terahertz, and infrared regimes using conventional materials. Devices designed for operation at these wavelengths are incredibly valuable across various applications such as material characterization, imaging technologies, and communication systems. However, the scarcity of devices is attributed, in part, to the limited availability of naturally occurring materials that can operate in these ranges. Therefore, there is an exciting opportunity to tailor electromagnetic metamaterials for millimeter wave, terahertz, and infrared manipulation.Electromagnetic metamaterials have been shown to enable unique scattering effects leading to advancements in next-generation devices. One important feature of metamaterials is the ability to tune the geometry and engineer the scattered response for nearly any range of the electromagnetic spectrum. Therefore, the exploration and development of advanced electromagnetic metamaterials for use in millimeter wave, terahertz, and infrared regimes is of great importance.Chapter 1 provides a discussion on the importance of millimeter wave, terahertz, and infrared radiation. In addition, this chapter provides an introduction to electromagnetic metamaterials. Chapters 2 and 3 discuss two metamaterials designed for operation at millimeter wavelengths. In Chapter 2, a metamaterial coherent detector is presented and in Chapter 3, a metamaterial gradient index lens is introduced.Several metamaterials for operation in the terahertz range are studied and discussed in Chapter 4, 5, and 6. In Chapter 4, exotic physics is studied and results in the excitation of high-quality factor modes. Chapter 5 introduces an electromagnetic absorber for radiometric calibration applications. Lastly, Chapter 6 presents a metamaterial strain sensor. A reflective and transmissive metamaterial diffuser is studied in Chapter 7 for use in the infrared regime. An in-depth discussion on the fabrication of all presented metamaterials is included in Chapter 8. Finally, a summary of all presented works and concluding thoughts is included in Chapter 9.