The nanocomposite polyvinyl pyrrolidone (PVP) films containing Ag nanoparticles and Rhodamine 6G are prepared on the two-dimensional distinctive continuous ultrathin gold nanofilms. We investigate the optical properties and the fluorescence properties of silver nanoparticles-PVP polymer composite films influenced by Ag nanoparticles and Au nanoparticles. Absorption spectral analysis suggests th...

The localized surface-plasmon resonance of metal nanoparticles corresponds to a classical charge oscillation of the quasi-free conduction electrons. In the case of noble-metal nanoparticles, interband transitions from the d electrons influence the spectra strongly. In addition, the inhomogeneity of the nanoparticles at the atomistic level becomes important for small sizes. Using the time-evolut...

Coatings that can self-modulate their optical properties as a function of an external stimulus are of significant technological interest. In this regard, the possibilities for thermoor electrochromic materials such as V02 and W03 are already comparatively well-known. Here, however, we explore a new kind of 'smart' coating, based on the active control of a plasmon resonance in nanoparticles. One...

Controlling plasmon-exciton coupling through band gap engineering of plasmonic crystals is demonstrated in the Kretschmann configuration. When the flat metal surface is textured with a sinusoidal grating only in one direction, using laser interference lithography, it exhibits a plasmonic band gap because of the Bragg scattering of surface plasmon polaritons on the plasmonic crystals. The contra...

Electron energy-loss spectroscopy can be used for detailed spatial and spectral characterization of optical excitations in metal nanoparticles. In previous electron energy-loss experiments on silver nanoparticles with radii smaller than 20 nm, only the dipolar surface plasmon resonance was assumed to play a role. Here, applying electron energy-loss spectroscopy to individual silver nanoparticle...

The plasmon resonance of metal nanoparticles shifts upon refractive index changes of the surrounding medium through the binding of analytes. The use of this principle allows one to build ultra-small plasmon sensors that can detect analytes (e.g., biomolecules) in volumes down to attoliters. We use simulations based on the boundary element method to determine the sensitivity of gold nanorods of ...

We study the influence of optical near-field interactions on the dipole surface plasmon resonance of Au nanoparticles in closely spaced particle arrays using finite-difference timedomain simulations. In particular, the resonance energies of the collective plasmon-polariton modes are determined for longitudinal and transverse polarization for different particle array lengths and inter-particle s...

The propagation of a plasmon surface wave in deep metallic lamellar gratings is shown to be characterized by absorption losses smaller than on a flat metallic-dielectric interface. This feature is due to the formation of a resonance of the electric field inside the groove. Similar to the plasmon surface wave in shallow gratings, this kind of plasmon can lead to total absorption of incident ligh...

Surface plasmon resonances on bilayer aluminum nanowire gratings are studied in both theory and experiment. It is found that there are two kinds of surface plasmon on the bilayer metallic gating: longitudinal aluminum/dielectric/aluminum slit and lateral aluminum/dielectric interface waveguide mode. The surface plasmon waveguide mode resonance in the slits makes the grating act as a transverse ...