Linear optical response of a quantum dot ‒ metal nanoshell hybrid system

• Published in: Physica. E, Low-dimensional systems & nanostructures Low-dimensional systems & nanostructures, 2023-04, Vol.148, p.115625, Article 115625
• Main Authors: Kontakos, Alexandros, Paspalakis, Emmanuel, Kosionis, Spyridon G.
• Format: Article
• Language: English
• Subjects: Dielectric core; Linear susceptibility; Metal nanoshell; Plasmonic nanostructure; Semiconductor quantum dot
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2022.115625

We investigate the linear optical response in a hybrid nanostructure composed of a semiconductor quantum dot located in proximity to a core-shell metal nanoparticle. Using the density matrix approach, we derive analytical expressions for the linear optical susceptibility of the two components of the nanostructure, which are dependent on the geometrical characteristics of the metal nanoshell, on the material of both the dielectric environment and the dielectric core, as well as on the polarization direction of the incident electric field and the distance separating the two nanoparticles. As a result, the characteristics of the absorption and the dispersion spectra of the semiconductor quantum dot and the metal nanoshell are determined by these parameters. The nanosystem under investigation shows significant gain without population inversion in the semiconductor quantum dot. A comparison of the results of this nanosystem with that containing a metal nanosphere is also presented. •The absorption and dispersion spectra in a coupled quantum dot – core/shell metal nanoparticle structure is analyzed.•A dielectric core – metallic shell nanoparticle is considered.•The influence of the geometric characteristics of the hybrid structure on the absorption and dispersion spectra is analyzed.•The effect of the dielectric environment on the absorption and dispersion spectra is also presented.