t e

ing row o lattice o guide. T the tren various s son betw Previo concentr the cons for propagation losses.5 Recently, the effects of scat-tering at sidewall roughness in PhC slabs were studied in a two-dimensional model.6 In this work we consider the variation of hole radii as the main disorder effect. The present fully three-dimensional results extend those of Ref. 7, in which only intrinsic losses above the light line were calculated and the effect of disorder was not included. After discussing the model and the nu-merical results, we compare them with recent experi-mental measurements of losses below the light line.8,9 Fig. 1. (a) Dispersion of the defect mode; the dotted line is the air light line. (b) Imaginary part of the frequency for different values of disorder parameter Dra. Parameters of the W1 air-bridge structure are ra 0.28, da 0.5, ecore 12, eair 1.f holes along the GK direction in a triangular f airholes, which is also called a W1 wave-he main purpose of this Letter is to quantify ds of disorder-induced losses as a function of tructure parameters and to make a compari-een air-bridge and SOI PhC slabs. us studies of disorder phenomena in PhC slabs ated on the effects on the photonic gap4 or on equences of a nonvertical shape of the holesDisorder-induced losses in pho line