Satellite peaks in the scattering of p-polarized light from a randomly rough film on a perfectly conducting substrate

The diffuse scattering of p-polarized light from a one-dimensional, randomly rough dielectric film deposited on a planar, perfectly conducting surface is studied by means of small-amplitude perturbation theory. The dielectric constant εd and the thickness d of the dielectric film are chosen in such a way that in the absence of roughness the scattering system supports N (≥ 2) guided modes whose wavenumbers are q 1 (ω), …,q N(ω) at the frequency ω of the light incident at an angle θo. We investigate the occurrence of satellite peaks, in addition to the enhanced back-scattering peak, in the angular distribution of the intensity of the diffusely scattered light, at angles θs(n, m) given by sin θs(n, m)= − sin θ0± (c/ω) [Qn(ω) − qm(ω)] for n, m=1, …, N(n ≠ m). These satellite peaks are multiple-scattering effects due to degenerate timereversal symmetry.