Infrared Metamaterial Absorbers

Abstract

Realization of an ideal electromagnetic absorber has long been a goal of engineers and is highly desired for frequencies above the microwave regime. On the other hand, the desire to control the blackbody radiation has long been a research topic of interest for scientists--one particular theme being the construction of a selective emitter whose thermal radiation is much narrower than that of a blackbody at the same temperature. In this talk, I will present the computational and experimental work that was used to demonstrate infrared metamaterial absorbers and selective thermal emitters. Based on these work, we further demonstrate an electrically tunable infrared metamaterial absorber in the mid-infrared wavelength range. A voltage potential applied between the metallic portion of metamaterial array and the bottom ground plane layer permits adjustment of the distance between them thus altering the electromagnetic response from the array. Our device experimentally demonstrates absorption tunability of 46.2% at two operational wavelengths. Parts of this thesis are based on unpublished and published articles by me in collaboration with others. The dissertation author is the primary researcher and author in these publications. The text of chapter two, chapter five, and chapter seven is, in part, a reprint of manuscript being prepared for publication. The text of chapter three is, in part, a reprint of material as it appears in Physical review letters 104 (20), 207403. The text of chapter four is, in part, a reprint of material as it appears in Physical Review Letters 107 (4), 45901. The text of chapter six is, in part, a reprint of material as it appears in Applied Physics Letters 96, 011906