作者:Yao, XL (Yao, Xiaoli)
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
3D asymmetric structure could induce asymmetric diffraction with spatial coupling behavior for various optical applications, but the study still faces challenges due to the complicated local-field coupling mechanism within structures. In this study, the spatial asymmetry based on inclined all-dielectric structure was theoretically modeled. The normal reflection of the 2D array shows that the increasing structural inclination selectively enhances the Fano resonance between different polarization directions which is mainly due to the oriented spatial coupling effect by increasing structural asymmetry, proved with the near-field distribution. The angular-resolved reflection shows the selected enhancement of first-order diffraction even over that of zero order by combining the structural asymmetry and oblique incidence. Our study provides a new insight for exploring asymmetric photonic structures and relative devices in practical applications.