Asymmetry reversal and waveguide modes in photonic crystal slabs

E. F. C. Driessen, P. O. M. Heemskerk, D. Stolwijk, E. W. J. M. van der Drift, M. J. A. de Dood, Richard M. De La Rue, Ceferino López, Michele Midrio, Pierre Viktorovitch
2008 Photonic Crystal Materials and Devices VIII  
The measured reflection spectra of two-dimensional photonic crystal slabs consist of an asymmetric peak on top of an oscillating background. For p-polarized light, the asymmetry of the peak flips for angles of incidence beyond Brewster's angle. We explain the observed line shapes with a Fano model that includes loss and use a waveguide model to predict the resonance frequencies of the photonic crystal slab. Finite-difference time domain calculations support the model and show that the resonance
more » ... due to a higher order mode disappears when the substrate refractive index is increased beyond n s = 2.04. This is readily explained by the cut-off condition of the modes given by the waveguide model.
doi:10.1117/12.780455 fatcat:yvcojabyevfpnhaxh75as4h3hi