Ultrabroad resonance of localized plasmon on a nanoparticle coupled with surface plasmon on a nanowire enabling two-photon excited emission via continuous-wave laser
arXiv:2504.13417 · doi:10.1063/5.0276443
Abstract
This study found that plasmonic hotspots (HSs) between silver nanoparticles (NPs) and silver nanowires (NWs) generated two-photon excited emissions, including hyper-Rayleigh, hyper-Raman, and two-photon fluorescence of dye molecules with continuous-wave (CW) near-infrared (NIR) laser excitation. A comparison between experimental results and electromagnetic (EM) calculations revealed that a large EM enhancement factor (FR) at the HS appears in the visible to NIR regions owing to EM coupling between localized plasmons of the NP and surface plasmons of the NW. This ultrabroad resonance of the coupled plasmons enables the observation of two-photon-excited emissions with CW laser excitation. A comparison of the dependence of the NP diameter, NW diameter, and gap distance on two-photon-excited emissions further demonstrated that the large HS-by-HS variations in the emission intensities were mainly induced by the sensitivity of FR to the gap distance at the HSs. We also experimentally and theoretically investigated the propagation of two-photon-excited emission light to a neighboring NP on the NW via surface plasmons.
54 pages, 18 figures
References in corpus (11)
- Surface-enhanced Raman scattering and fluorescence near metal nanoparticles
- Absorption cross-section spectroscopy of single strong coupling system between plasmon and molecular exciton resonance using single silver nanoparticle dimer generating surface enhanced resonant Raman scattering
- Directional out-coupling of light from a plasmonic nanowire-nanoparticle junction
- Anti-crossing properties of strong coupling system of silver nanoparticle dimers coated with thin dye molecular films analyzed by classical electromagnetism
- Propagation mechanism of surface-enhanced resonant Raman scattering light through one-dimensional plasmonic hotspot along silver nanowire dimer junction
- Spectral correlation between surface-enhanced resonant Raman and far field scattering destructed by dipole quadrupole coupled plasmon resonance
- Correlated polarization dependences between surface-enhanced resonant Raman scattering and plasmon resonance elastic scattering showing spectral uncorrelation to each other
- Electromagnetic enhancement generated by Ap term of cavity quantum electrodynamics demonstrated by single coupled systems between plasmon and molecular exciton
- Electromagnetic enhancement of one-dimensional plasmonic hotspots along silver nanowire dimer examined by ultrafast surface enhanced fluorescence
- Momentum-resolved surface enhanced Raman scattering from a nanowire-nanoparticle junction cavity
- Plasmon-enhanced two photon excited emission from edges of one-dimensional plasmonic hotspots with continuous-wave laser excitation