Large and Versatile Plasmonic Enhancement of Photoluminescence Using Colloidal Metallic Nanocubes

TL;DR

This study demonstrates that colloidal silver nanocubes can significantly enhance the photoluminescence of various materials, achieving up to 200-fold increase, by improving light injection and extraction through plasmonic effects.

Contribution

It introduces a versatile colloidal nanocube approach for boosting photoluminescence efficiency across different materials, with detailed analysis of key parameters.

Findings

Photoluminescence of YAG:Ce increased by 80% with optimal nanocube density.

Quartz's fluorescence signal was enhanced by a 200-fold factor.

Surface density and disorder of nanoparticles are critical for enhancement.

Abstract

Improving phosphor photoluminescence efficiency is a key parameter to boost the performances of many optical devices. In this work, colloidal silver nanocubes, homogeneously spread on a luminescent surface, have proved to help both injecting and extracting light in and out of the photoluminescent layer and hence contributed significantly to the enhancement of the fluorescence. This approach has been applied to two materials: the well-known Y$_3$Al$_5$O$_{12}$:Ce yellow phosphor and an optical quartz. The emission efficiency, for sol-gel derived YAG:Ce layers, has increased of 80\% in the presence of an optimal nanoparticle density -- whereas for quartz, a weakly fluorescent material, the photoluminescence signal can be enhanced by a 200-fold factor. A physical analysis based on simulations shows that the disorder is an important factor and that the surface density of Ag nanoparticles is a crucial parameter.