Development and characterization of metallo-dielectric hybrid nanomaterials

Abstract

The rational combination of dielectric and metallic nano particles brings novel optical properties to conventional subwavelength structures. This thesis introduces the optoplasmonic geometries demonstrating versatile ability in both far and near field modification within nano scale. Template-assisted self-assembly approaches are applied creating nano entities with titanium dioxide and gold nano spheres. A top-bottom mono hybrid unit and interdigitated array are developed. With the examination of the elastic and inelastic response of these hybrid materials, physical models are simulated to depict the scenario of varied geometry and combination of nano particles. In contrast to solely metal or dielectric particle arrays, this type of artificial material not only enhances the near electric field intensity within the metal nano cluster hot spots, but also expands the overall volume of enhanced electric field. Further study reveals that the additional enhancement and redistribution of near field are derived from the coupling between the nano gold cluster plasmon resonance and the in-plane diffractive mode of the dielectric array. The redirected emission profile of the fluorescent dyes within the hybrid array is explored.