Dynamic Metasurfaces for Advanced Applications

Abstract

To date metamaterials and metasurfaces have been studied for over 20 years. Throughout this time sophisticated understanding of their properties and capabilities has been developed, with many significant and exotic properties such as flat lenses, negative refraction, and perfect absorption. In this work significant advances are made in two main areas. First we explore the subject of the all dielectric metasurface, implemented as arrays of dielectric cylinders. Here, we improve upon the current understanding of absorption in all-dielectric metasurfaces; we demonstrate the significance of periodicity, outlining special properties of the dielectric metasurface, and finally we apply developed knowledge about mode confinement in the dielectric metasurface to a novel system utilizing phase change materials. Second, traditional metal-insulator-metal metasurfaces with advanced capabilities are developed. We utilize the electronic compatibility of the MIM system to incorporate spatio-temporal modulation, enabling a new class of nonreciprocal reflectarrays. Finally we present a general, algorithmic optimization that brings our nonreciprocal metasurface to application-relevant efficiencies.