Design And Implementation Of Metasurface Based On Dielectric Materials

In recent years, metasurfaces have received widespread attention in a series of modulation of electromagnetic waves, therefore metasurface’s design and implementation and how to effectively increasing the dynamic modulated mechanism in metasurface is a very important research direction. When the beam passes through a conventional optical device, the light beam wavefront produces a corresponding continuous phase accumulation with optical path increasing. This is a traditional optics for beam modulation physical mechanism. The beam modulation principles of metasurfaces is introduced by phase shifts in the metasurface. The different materials and shapes of antennas determines the performance of metasurface. So far, most metasurfaces are made of low coupling efficiency and high loss metal antennas, and they work in low efficiency and work in the form of a fixed transmission mode. In this paper, based on rectangular silicon antennas, we design different metasurfaces and research on a variety of optics metasurfaces, including linear polarization converter, beam deflector, flat cylindrical lens, dynamic controlling focal length of plane cylindrical lens.Firstly, the resonance characteristics of the dielectric material particles is obtained by using electromagnetic waves theory analysis. We study the resonance of nanoparticles and the interaction response characteristics of media with electromagnetic wave. It introduces the silicon antenna unit structure, calculates the resonance properties of antenna silicon in the near infrared and shows the design of silicon antenna in the infrared reflection,which has produced two resonant peaks. It provides the basis for antenna analysis.Secondly, based on silicon antenna resonance characteristic in the infrared, we analyze the scattering characteristics of various geometrical parameters on the silicon of the antenna. It provides a very good foundation. For designing phase type metasurfaces of various functions, the different geometric parameters of silicon antenna elements has been using to combine metasurfaces. Using selected out of eight different structures of silicon antennas, we design with different functions metasurfaces, calculate the various properties of different functions metasurface, and obtain the performance parameters of different functions metasurfaces. By using the temperature characteristics of nematic liquid crystal, we design and implement a dynamic controlling focal length of plane cylindrical lens.Finally, we prepare the designed metasurface sample. By electron beam evaporation machine, the antenna structure functional layers of different films are deposited. At the same time, the optical parameters of silicon thin film is measured by the spectroscopic ellipsometry. By electron beam lithography technology, we produce metasurface pattern mask. By cleaning the surface of resist, we obtain metasurface sample’s mask.Using inductive couple plasma reactive ion etching machine, metasurface structure pattern is obtained by etching silicon film.