ATR excitation of surface polaritons at the interface between a metal and a layer of nanocrystal quantum dots

TL;DR

This paper investigates the resonance coupling between surface plasmon-polaritons and excitons in nanocrystal quantum dots at a metal/quantum dot interface, enabling selective excitation and control of light emission based on quantum dot size.

Contribution

It introduces a method to exploit ATR structures for selective excitation of quantum dots via plasmon-exciton coupling, advancing optical control techniques.

Findings

Resonance coupling significantly affects optical properties.

Selective excitation of quantum dots of different sizes is possible.

Control over emitted light intensity and color is demonstrated.

Abstract

Surface plasmon-polaritons in a multilayer structure consisting of a metallic film and one or more layers of nanocrystal (NC) quantum dots (QDs) are studied. It is shown that there is resonance coupling between the plasmon-polaritons propagating along the metal/NC-layer interface and excitons confined in the dots, which makes a considerable effect on the optical properties of the structure unless the dispersion of the QD size is too large. This coupling can be explored in order to selectively excite QDs of different size by using an attenuated total reflection (ATR) structure. It opens the possibility of control of the relative intensity of light of different color, emitted by the QDs of different size.