Ag colloids and arrays for plasmonic non-radiative energy transfer from quantum dots to a quantum well

TL;DR

This study demonstrates plasmon-mediated non-radiative energy transfer from quantum dots to quantum wells using Ag colloids and arrays, achieving up to 25% efficiency and tunable interactions based on nanoparticle geometry.

Contribution

It introduces a novel approach using Ag colloids and arrays to control and enhance energy transfer between quantum dots and quantum wells.

Findings

Energy transfer efficiency up to ~25% with Ag colloids.

Distance dependence follows d^{-4} consistent with F"orster-like behavior.

Array geometry influences emission quenching and enhancement.

Abstract

Ag nanoparticles in the form of colloids and ordered arrays are used to demonstrate plasmon-mediated non-radiative energy transfer from quantum dots to quantum wells with varying top barrier thicknesses. Plasmon-mediated energy transfer efficiencies of up to ~25% are observed with the Ag colloids. The distance dependence of the plasmon-mediated energy transfer is found to follow the same d^{-4} dependence as the direct quantum dot to quantum well energy transfer. There is also evidence for an increase in the characteristic distance of the interaction, thus indicating that it follows a F\"orster-like model with the Ag nanoparticle-quantum dot acting as an enhanced donor dipole. Ordered Ag nanoparticle arrays display plasmon-mediated energy transfer efficiencies up to ~21%. To explore the tunability of the array system, two arrays with different geometries are presented. It is demonstrated that changing the geometry of the array allows a transition from overall quenching of the acceptor quantum well emission to enhancement, as well as control of the competition between the quantum dot donor quenching and energy transfer rates.