We report theoretical evidence that bulk nonlinear materials weakly interacting with highly localized plasmonic modes in ultra-sub-wavelength metallic nanostructures can lead to nonlinear effects at the single plasmon level in the visible range. In particular, the two-plasmon interaction energy in such systems is numerically estimated to be comparable with the typical plasmon linewidths. Locali...

In this paper, a fast and sensitive localized surface plasmon resonance (LSPR) based biosensor was developed and the optimization of gold – antibody conjugates through investigation of different parameters were performed. Gold nanoparticles (AuNPs) with a size of ~20 nm were synthesized via chemical reduction of HAuCl4 with trisodium citrate as reducing and stabilizing agent. The impacts of pH ...

We demonstrate strong exciton-plasmon coupling in silver nanodisk arrays integrated with monolayer MoS2 via angle-resolved reflectance microscopy spectra of the coupled system. Strong exciton-plasmon coupling is observed with the exciton-plasmon coupling strength up to 58 meV at 77 K, which also survives at room temperature. The strong coupling involves three types of resonances: MoS2 excitons,...

In this Letter, we report on dark field imaging of localized surface plasmon polaritons (SPPs) in plasmonic waveguiding bands formed by plasmonic coupled cavities. We image the light scattered from SPPs in the plasmonic cavities excited by a tunable light source. Tuning the excitation wavelength, we measure the localization and dispersion of the plasmonic cavity mode. Dark field imaging has bee...

Nowadays, hydrogen has attracted significant attention as a next generation clean energy source. Hydrogen is highly flammable, so detection of hydrogen gas is required. Gold nanoparticle based localized surface plasmon resonance (LSPR) is an advanced and powerful sensing technique, which is well known for its high sensitivity to surrounding refractive index change in the local environment. We p...

Localized surface plasmon resonance (LSPR) spectroscopy of metallic nanoparticles is a powerful technique for chemical and biological sensing experiments. Moreover, the LSPR is responsible for the electromagnetic-field enhancement that leads to surface-enhanced Raman scattering (SERS) and other surface-enhanced spectroscopic processes. This review describes recent fundamental spectroscopic stud...