Resonant Scattering of Surface Plasmon Polaritons by Dressed Quantum Dots

The resonant scattering of surface plasmon-polariton waves by embedded semiconductor quantum dots above the dielectric/metal interface is explored in the strong-coupling regime. In contrast to non-resonant scattering by a localized dielectric surface defect, a strong resonant peak in the scattering field spectrum is predicted and accompanied by two side valleys. The peak height depends nonlinearly on the amplitude of surface plasmon-polariton waves, reflecting the feedback dynamics from a photon-dressed electron-hole plasma inside the quantum dots. This unique behavior in the scattering field peak strength is correlated with the occurrence of a resonant dip in the absorption spectrum of surface plasmon-polariton waves due to interband photon-dressing effect. Our result on the scattering of surface plasmon-polariton waves may be experimentally observable and applied to spatially selective illumination and imaging of individual molecules.