Instantaneous and steady-state field analysis. Time evolution of a Gaussian pulse propagating inside the 3D PhC (along the z- propagation direction, at the center of the xy- plane), for three frequencies: (a) a/λ = 0.450, (b) a/λ = 0.468 and (c) a/λ = 0.496. (d) Broadband steady-state field intensity distributions at the same propagation line. Steady-state field distributions obtained at the xz- plane of the center of the y- direction for the normalized operational frequencies equal to (e) a/λ = 0.450, (f) a/λ = 0.468 and (g) a/λ = 0.496. The magnitude of the field intensities are normalized by dividing the calculated intensities to the intensity produced by the source at the specific frequencies. The distances in the z- propagation direction are given with respect to the position of the source.