Photoluminescence Enhancement of CuInS₂ Quantum Dots in Solution Coupled to Plasmonic Gold Nanocup Array

Abstract

A strong plasmonic enhancement of photoluminescence (PL) decay rate in quantum dots (QDs) coupled to an array of gold-coated nanocups is demonstrated. CuInS QDs that emit at a wavelength that overlaps with the extraordinary optical transmission (EOT) of the gold nanocup array are placed in the cups as solutions. Time-resolved PL reveals that the decay rate of the QDs in the plasmonically coupled system can be enhanced by more than an order of magnitude. Using finite-difference time-domain (FDTD) simulations, it is shown that this enhancement in PL decay rate results from an enhancement factor of ≈100 in electric field intensity provided by the plasmonic mode of the nanocup array, which is also responsible for the EOT. The simulated Purcell factor approaches 86 at the bottom of the nanocup and is ≈3-15 averaged over the nanocup cavity height, agreeing with the experimental enhancement result. This demonstration of solution-based coupling between QDs and gold nanocups opens up new possibilities for applications that would benefit from a solution environment such as biosensing.

PbS Colloidal Quantum Dot Inks for Infrared Solar Cells

“…To improve the infrared photovoltaic performance of CQDSCs, various metal chalcogenide CQDs were studied, including PbS ( Cademartiri et al., 2006 ), PbSe ( Zhang et al., 2017a , 2017b , 2017c ), Ag 2 S ( Hwang et al., 2013 ), Ag 2 Se ( Tian et al., 2017 ), CuInS 2 ( Peer et al., 2017 ), and AgBiS 2 ( Huang et al., 2013 ) CQDs. Among these CQDs, PbS CQDs received more attention for the development of infrared solar cells in the wavelength region of 350–1,700 nm ( E g < 0.8 eV) and the PbS-based CQDSCs showed the highest efficiency of CQDSCs so far, which is very promising for the infrared solar cells.…”

Diameter-optimized high-order waveguide nanorods for fluorescence enhancement applied in ultrasensitive bioassays

“…An alternative and far more promising strategy to address this challenge would be to develop novel fluorescence enhancement (FE) platforms, which lately have sparked enormous interest. [22][23][24][25][26][27][28][29][30] A big variety of FE platforms, including silver nanoparticles, gold nanoparticles/nanorods (NRs), Si/SiO2 nanopillars, GaP nanowires, ZnO NRs, etc. have been successfully fabricated and studied.…”

“…have been successfully fabricated and studied. [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] Amongst them, ZnO NRs-based FE platforms are particularly fascinating in bioassays, thanks to their well-recognized benefits, such as prevention from fluorescence quenching, no optical absorption in the entire visible to near-infrared region, relatively large refractive index, controllable morphology and alignment, facile fabrication, and low cost. [37][38][39][40] It is therefore no surprise that enormous effort has been devoted to improve the detection performance of ZnO NRs-based FE platforms through various morphology and surface/interface modification.…”

High‐Efficiency Optical Filters Based on Nanophotonics

“…Since the discovery of anomalous transmission phenomena based on surface plasmons by Ebbesen et al in 1998 [122], plasmonic wavelengthselective filters using metal nanostructures have been actively studied [123][124][125][126][127]. In recent years, the fabrication technology of metal nanostructures by nanoimprint technology has advanced [128][129][130][131][132][133][134][135][136][137][138], and it is expected that the productivity of plasmonic nanostructures will be improved.…”