Abstract: Disclosed are layered nanoparticles including multiple dopants constrained in discrete layers of the particles. Through predetermination of the architecture of the nanoparticles, energy transfer between the active ions can be controlled. Active ions can be provided in discrete sections of the nanoparticles so as to allow complete, partial, or no energy transfer between the optically active ions. In one embodiment, the emission spectra of a single nanoparticle can be equivalent to the spectrum of a blend of singularly doped nanoparticles, providing for composite materials with improved homogeneousness and multiple emissions from a single excitation wavelength. The layered nanoparticles can be, for example, core/shell nanoparticles.

Abstract: The present invention is directed to optical devices. More specifically, the disclosed devices include a film defining a periodic array of surface elements so as to give rise to surface plasmon polaritons. The film also includes at least a single aperture having a diameter less than the wavelength of light. In one embodiment, the surface elements can be an array of anisotropic apertures and the films can act as a polarizer. The disclosed devices can also include a material having a variable refractive index substantially adjacent to the metal film. For example, the refractive index of the adjacent material can vary according to some characteristic of the light incident to the device, for instance, the intensity or the angle of incidence of the light. In this embodiment, resonant coupling of incident light with the SPP, and hence transmittivity of the device, can depend upon the nature of incident light.

Abstract: The present invention is directed to optical devices. More specifically, the disclosed devices include a film defining a periodic array of surface elements so as to give rise to surface plasmon polaritons. The film also includes at least a single aperture having a diameter less than the wavelength of light. In one embodiment, the surface elements can be an array of anisotropic apertures and the films can act as a polarizer. The disclosed devices can also include a material having a variable refractive index substantially adjacent to the metal film. For example, the refractive index of the adjacent material can vary according to some characteristic of the light incident to the device, for instance, the intensity or the angle of incidence of the light. In this embodiment, resonant coupling of incident light with the SPP, and hence transmittivity of the device, can depend upon the nature of incident light.