Generalizing Dipolar Model for the Characterization of Substrated Periodic Metasurfaces Under Oblique Illumination

Most metasurfaces are fabricated on dielectric substrates and have found various applications in manipulating the characteristics of incident fields, from any direction that is normal or at oblique incidences. As a result, a precise analysis of substrated metasurfaces under oblique illuminations is very attractive and important. In this article, the theory of the analytical modeling of periodic planar metasurfaces, placed on a dielectric substrate for normal incidence, is extended to general oblique cases. This method is based on an independent analysis of the electromagnetic behavior of the constituent particles and the interactions of the particles with each other. Since the interaction coefficients are calculated analytically, this method is time effective. The reflectance and transmittance of different substrated metasurfaces under oblique incidence, which is obtained from our proposed method, are compared to the results of numerical full-wave simulations. Two different cases are considered here—a metasurface consisting of isotropic spherical particles and a more general case of a bianisotropic metasurface composed of SRR inclusions. Good accordance has been observed between the results, confirming the accuracy of the proposed method. Furthermore, the effects of different parameters on the interaction coefficients are also investigated.