Enhanced spontaneous emission from two-photon-pumped quantum dots in a porous silicon microcavity

Abstract

Photoluminescence (PL)-based sensing techniques have been significantly developed in practice due to their key advantages in terms of sensitivity and versatility of the approach. Recently, various nanostructured and hybrid materials have been used to improve the PL quantum yield and the spectral resolution. The near-infrared (NIR) fluorescence excitation has attracted much attention because it offers deep tissue penetration and it avoids the autofluorescence of the biological samples. In our study, we have shown both spectral and temporal PL modifications under two-photon excitation of quantum dots (QDs) placed in one-dimensional porous silicon photonic crystal (PhC) microcavities. We have demonstrated an up-to-4.3-fold Purcell enhancement of the radiative relaxation rate under two-photon excitation. The data show that the use of porous silicon PhC microcavities operating in the weak coupling regime permits the enhancement of the PL quantum yield of QDs under two-photon excitation, thus extending the limits of their biosensing applications in the NIR region of the optical spectrum.

Enhanced fluorescence emission of a single quantum dot in a porous silicon photonic crystal—plasmonic hybrid resonator

“…Today, combining PNPs and pSiMCs is a promising approach for enhancing photoluminescence of emitters through strong light-matter coupling for a wide range of potential applications, including photocatalysis, sensing, displays, and quantum informatics. However, optimal parameters of these photonic devices still need to be determined for their development and improvement of their performance [15][16][17][18][19]. Here, we simulated these hybrid systems using the finite element method (FEM), a numerical method widely used in various fields [20].…”

A MSM Visible-near-Infrared Wavelength Photodetector Based on PbS Quantum Dots/Porous Silicon Hybrid Structure

“…PbS quantum dots (QDs) with ~3 nm diameter has a significant quantum effect, and its emission spectrum can cover the near-infrared band range. In addition, the PbS QDs has a good photoelectrical performance with high color purity, good stability and easy mass production [14], thus they have been utilized for biological and other detection [15]. Gaur et al have investigated highly sensitive dual-mode labeled detection of biotin using reflection interference and fluorescence generated by conjugations of QDs-biotin and streptavidin probes immobilized on the PSi pore walls [16].…”

Enhancement of Quantum Dot Fluorescence by a Metal Nanoparticle/Porous Silicon Microcavity Hybrid System

“…Combining microcavities and plasmon nanoparticles is a promising approach to obtaining hybrid systems with improved light emission due to strong light-matter coupling. However, the structure of the corresponding photonic devices should be further optimized [1][2][3][4][5].…”