In-plane radiation pattern generated by large particles in dielectric substrates

In this work we present the study of in-plane radiation patterns generated by particles with dimensions larger than the excitation wavelength. We studied the in-plane radiation of Au structures focusing on two cases: particles and triangular crystals. We found that the radiation patterns were produced by the scattering of the excitation field at the bottom edges of the studied structures. In addition, we found the in-plane radiation decay exponentially due to the refractive index contrast between the substrate and superstate. Furthermore, we proved that in-plane radiation patterns originating from different structures can interact and generate interesting geometries. Finally, in addition to our experimental studies, we show numerically calculated simulations which agreed with our experimental results and thus confirmed our findings.