Optical Metasurfaces

Abstract

This thesis aims at introducing different optical metasurfaces specifically designed to achieve subwavelength focusing in the infrared range. Most of the plasmonic research in the literature has been directed towards the visible range and little attention was given to infrared metasurfaces and their applications. In this thesis, we have presented three different metasurfaces that can achieve sub-wavelength focusing in the infrared domain. The structures presented achieve either high focusing resolution or high transmission efficiency or extended mid-infrared bandwidth so they can satisfy the different critical requirements of different infrared applications. We study and compare their performance parameters across the wavelength and we also study the influence of the used metal’s permittivity on the transmission performance. Those studies and comparison are meant to provide future designers an insight on how to design the metasurfaces that suit their performance requirements in the infrared range. They are also meant to make the design process easier.