Oblique illumination-induced transformation between the FP and the Fano resonances through an all-dielectric metasurface.

Abstract

We demonstrate the angular dispersive transmission properties of electromagnetic fields with both the Fabry-Pérot (FP) resonances and Fano resonances through an all-dielectric metasurface consisting of a silicon bar array over the silicon dioxide slab. More specifically, when the normal incidence is casting over the metasurface, solely FP resonances will be achieved, and the silicon rod array can be equivalent to another dielectric combining with the silicon dioxide substrate. On the other hand, the Fano resonances will become dominant when the metasurface is under the wide-angular oblique illumination, raising the asymmetry in the silicon bar array to function as toroidal dipoles and electric quadrupoles and thus enable the proposed all-dielectric metasurface to achieve different resonances with the variation of different angular illuminations.