Babinet Metasurface Design And Applications In Manipulating Surface Plasmon Polaritons

Surface plasmons polaritons(SPPs)are electromagnetic excitations bound to the metal-dielectric interfaces.Because their field enhancement effect is based on the strong interaction of electrons and waves on the metal surface,they can break the limit of diffraction.Owing to the ability of manipulating light propagation and diffusion in the nanoscale,SPPs have huge potential in the application of photoelectric integration.The recent researches have revealed that metasurfaces provide an elegant way to arrange the spatial distributions of light in a prescribed manner.They can also allow a new degree of freedom to regulate the local light-matter inter interactions and shape the wavefront of SPPs.However,most metasurface structures consist of metal pattern printed on the dielectric substrate,which is incompatible with the metallic structures for SPPs generation.Based on Babinet principle,C-shaped periodic apertures were designed in this thesis.The radiation of the SPPs can be controlled by their different orientations on the metal surface.Compared to the metasuface with slits arrays,the proposed C-shaped apertures metasurface can generate SPPs with uniform amplitude distribution independent of the rotation angle.By precise structure design,the C-shaped metasurface can achieve a phase control in the launching process to manipulate the radiation of SPPs.A directional SPPs launching as well as focusing/diverging effect is achieved along the Babinet metasurface.This methodology promises the flexibility to control the shape of the SPPs and realize the anomalous phase-control.Furthermore,a microwave absorbing device based on reconfigurable metasurface is also proposed.The control part provides reverse bias voltage to the variode in each metasurface unit cell,thus realizing independent control of electromagnetic response.By designing the phase matrix on the metasurface,anomalous reflection as well as absorbing effect can be achieved.This simple designed,easy machining and high integrated structure has strong applied value in the regulation of electromagnetic wave.