Analysis of photonic crystal waveguide devices

M.D.B.Charlton, M.C.Netti, M.E.Zoorob, G.J.Parker, J.J.Baumberg,

In this poster we present detailed experimental measurements of the spectral properties of photonic crystals etched into the core layer of planar Silicon Nitride waveguide structure. Despite the relatively low refractive index contrast between the pores and the holes, these structures are shown to possess a polarisation insensitive and non-directional band-gap at visible wavelengths. Highly dispersive features in good agreement with plane wave simulation models are also noted.

Investigations were performed into the rate of attenuation of transmitted (waveguiding) modes as a function of the number of rows of pores. Measurements were also performed on waveguides with different core thickness in order to determine which spectral artifacts are strongly related to the 3-dimensional nature of the confining waveguide structure. Comparisons are made with 3-dimensional modelling methods.

Photonic crystal waveguide devices incorporating line-defect waveguides and bends have also been fabricated and measured. Preliminary spectral results suggest that the surrounding photonic crystal lattice significantly modifies the lateral mode structure of the waveguide bend, as predicted by theory. Comparisons are made with FDTDM simulations.