Localization of Surface-Exciton Polaritons

We develop a numerical model to investigate the localization of surface-exciton polaritons in the presence of random roughness and spatial dispersion. It is found that the localization occurs in a limited frequency range near the maximum frequency of surface-exciton polaritons. The decaying length in the extended region is much larger than that in the localized region. The localization of surface-exciton polaritons is due to the destructive interference between waves scattered from the rough surface.