Controlling the Luminescence of Quantum Dots in Hybrid Structures Based on Porous Silicon

Abstract

Resonant cavities based on porous silicon (pSi) are of interest as a basis for hybrid photoluminescent (PL) systems from the viewpoints of both fundamental and applied research. One of the most promising fluorophores for creating such hybrid systems is semiconductor quantum dots (QD), due to their narrow PL spectra and broad absorption spectra. Depending on the structure and parameters of a hybrid system, polariton states can be created and the PL properties of the embedded fluorophores can be modified. This work describes a 4.4-fold narrowing of the PL spectrum of CdSe/ZnS semiconductor quantum dots (core/shell) and a 3.7-fold acceleration of spontaneous emission in pSi microcavities, relative to similar parameters of QDs in a solution. The observed changes in the PL properties of QDs are attributed to the interaction of light and matter between the microcavity eigenmode and the QD excitons. The obtained results pave the way for developing new photonic and optoelectronic devices.