Microstructured photonic crystal membranes are of great interest as compact filters in a variety of fields, including telecommunication and sensing. Here we present an analysis of the transmission and resonance behavior of a dielectric membrane featuring periodically arranged holes using the frequency domain finite element analysis. We solve both the source as well as eigenvalue problem for a given geometry. Applying symmetry considerations, we discard modes that cannot be excited by incident transverse electro-magnetic (TEM) light simultaneously. We relate the results of the source problem to the modal analysis and obtain strong correspondence in both frequency and resonance quality factor. We find that the sharp resonances can be related to the eigenmodes of a rectangular dielectric resonator formed by the membrane and the holes of the photonic crystal. Analyzing noncircular holes for polarization-dependent transmittivity, the modal analysis presented herein constitutes a powerful tool to understand and identify occurrence of pronounced wideband polarization selectivity.
© 2011 Optical Society of AmericaPDF Article