By modulating the glass network topology, the photoluminescence intensity of CsPbBr₃ QD-doped glasses can be enhanced by 8 times and the nonlinear absorption response can change from saturable absorption to reverse saturable absorption.

Ag nanoparticles (NPs) and ${\mathrm{CsPbBr}}_3$ perovskite quantum dots (QDs) are precipitated in a borosilicate glass by the conventional melt-quenching method, which has outstanding stability benefited from the amorphous oxide matrix. X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electronic microscopy results show that part of ${\mathrm{Ag}}^{+}$ ions replace ${\mathrm{Pb}}^{2+}$ ions in the ${\mathrm{CsPbBr}}_3$ QDs, and the other ${\mathrm{Ag}}^{+}$ ions convert into Ag NPs. The presence of these Ag-species results in enhanced photoluminescence total intensity by 5 times for the ${\mathrm{CsPbBr}}_3$ QD-doped glasses, explained by the accelerated growth of QDs and the Ag NPs-induced plasmonic near-field effect.

This work demonstrates the surface plasmon (SP)-exciton coupling effect on the photoluminescence (PL) enhancement in ${\mathrm{CsPbBr}}_3$ nanocrystal (NC) at PMMA/Ag nanostructure (NS) in wide spectral range excitation. The spectra dependent time resolved PL measurement reveals that the emission photons are from the recombination of localized excitons and the PL enhancement can be attributed to the near-field effect, which is also supported by evidence that the enhancements are nearly the same in the whole excitation wavelength from 200 nm to 900 nm. The non-spectral dependence of the enhancement factor suggests that there is the same dynamic process of hot electrons in ${\mathrm{CsPbBr}}_3$ NC in multiphoton excitation. The hot electrons will relax into localized exciton states, and the electric field generated by SPs will enhance the radiative recombination of excitons. This work will have benefits for revealing dynamics of hot electron relaxing and interactions in multi-photon absorption, as well as the inner mechanism of SP coupling effects.

A novel self-assembled hybrid nanocompound consisting of bismuth sulfide nanocrystals (${\mathrm{Bi}}_2{\mathrm{S}}_3$ NCs) and $\mathrm{Ag}@{\mathrm{SiO}}_2$ nanoparticles (NPs) is used to study the enhancement of photoluminescence by localized surface plasmon resonance (LSPR). $\mathrm{Ag}@{\mathrm{SiO}}_2$ core-shell NPs were prepared by deposition of silica onto the surface of Ag NPs through the sol–gel method and followed by surface modification via 3-aminopropyltriethoxysilane for the coming conjugation with ${\mathrm{Bi}}_2{\mathrm{S}}_3$ NCs. We propose the photoluminescence enhancement by the LSPR effect through adjusting the thickness of silica shell and the $\mathrm{Ag}@{\mathrm{SiO}}_2$ NP concentration. By modulating the thickness of the silica shell and the concentration of Ag NPs, the maximum enhancement of a 5.7 fold can be reached with the thickness of an ${\mathrm{SiO}}_2$ shell at 22.5 nm. A clear red shift of the emission peaks in the ${\mathrm{Bi}}_2{\mathrm{S}}_3$ NCs-$\mathrm{Ag}@{\mathrm{SiO}}_2$ NPs hybrid structures is observed. Such a metal-enhanced ${\mathrm{Bi}}_2{\mathrm{S}}_3$ quantum dot (QD) fluorescence system may have promising applications in optoelectronic device.