Propagation behavior of surface plasmons at the boundary between a thin metal film and a dielectric material influenced by the presence of quantum dots

Abstract

This study explores the dispersion properties of surface plasmons at the interface between a thin metallic film and a dielectric medium containing quantum dots (QDs) in a thin region near the metal–dielectric interface. Using the quantum hydrodynamic (QHD) model, we analyze the influence of quantum statistical (QS) and quantum diffraction (QDiff) effects on plasmonic dynamics. The system under investigation consists of a two-dimensional electron gas confined within a thin metallic film interacting with three-level quantum dots embedded in the adjacent dielectric medium. The excitonic states of the QDs couple with the surface plasmon electromagnetic field, modifying the dispersion relation through quantum coherence effects captured by the QHD model. These interactions enable tunable plasmonic properties, distinct from the classical dispersion of a metal–dielectric interface. Our findings reveal distinct dispersion characteristics governed by variations in electron density and dielectric properties. Notably, the introduction of a coupling field amplifies nonlinear effects, enabling enhanced sensitivity and tunability. This tunability is particularly significant for applications in surface-enhanced spectroscopy and super-resolution microscopy. The results offer valuable insights into the integration of quantum effects in plasmonic systems, with promising implications for nanophotonics and quantum technologies.