Noble metal nano particles sustaining collective oscillation of electrons (known as localized surface plasmons) have been vastly investigated and are promising in further optical signaling and chemical sensing application. However, such particle is suffering from intrinsic ohmic losses.Dielectric particle assemblies are able to redistribute the local electric field through geometry-dependent diffractive coupling and provide novel artificial medium for metal particles.
My research is aiming at designing, fabrication, characterization and implementation of rationally organized hybrid material composed of metallic and dielectric nano partitcles.
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.
The results demonstrate that in comparison with conventional metal or dielectric particle arrays, this is a new type of material which does not only enhance the near electric field intensity within the metal nano cluster hot spots, but also expand 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 dielectric array. This work brings new degree of freedom to metamaterials by positioning different type of components.
