Optical Characterization of Moiré Photonic Crystals Using the RCWA Method

In recent years the interest on Moiré structures have increased. Several engrossing phenomena in solid-state physics and photonics arise from these interference patterns. In this paper, we analyze the behavior of guided resonances of two simple Moiré structures made by superimposing two gratings. We calculate the transmittance spectra for s-polarization and p-polarization of light, using rigorous coupled wave analysis. The appearance of two guided resonances at perpendicular polarizations, for paralell displaced gratings, introduces the posibility of designing an optical device based on polarization of light. However, for twisted superimposed gratings, the abundance of peaks and dips in the transmittance spectra results in the lack of well-isolated guided resonances.