Theoretical and experimental study on surface modes of low symmetric periodic structures

In this study, surface waves supported at the boundary of two-dimensional all dielectric low-symmetric periodic structures (LSPS) are numerically investigated and experimentally verified in the microwave region. In LSPSs possessing more than one scattering element inside the unit cell, by modifying the secondary rods' positions, the surface corrugation is generated without altering the dielectric filling ratio of the structure. This modification initiates shifting of bands corresponding to the surface mode frequencies within the band gap. Thanks to the superior aspects of LSPSs, surface modes can be easily tuned in terms of the morphology of the unit cell elements. Manipulations of band gap-guided photons at the surface of the symmetry reduced photonic crystals hold potential to design new chemical and biological sensing applications and provide alternative routes for the realization of strong light and matter interactions.