Strong bonding magnetic plasmon hybridizations in double split-ring resonators.

The complex magnetic dipole plasmon couplings in double split-ring resonators are investigated. Two split peaks in the absorption spectrum of these coupled systems are observed, but even the shorter-wavelength resonance peak can be redshifted compared to the peaks of individual rings. The magnetic plasmon fields outside rings are found to play an important role in these strong couplings.

Fano resonances in dipole-quadrupole plasmon coupling nanorod dimers.

We theoretically investigate the plasmon coupling in metallic nanorod dimers. A pronounced dip is found in the extinction spectrum due to plasmonic Fano resonance, which is induced by destructive interference between the bright dipole plasmon of a short nanorod and the dark quadrupole plasmon of a long nanorod. This Fano interference can also be explained as the coupling between the bright and dark modes both supported by the whole dimer.

Tuning gold nanorod-nanoparticle hybrids into plasmonic Fano resonance for dramatically enhanced light emission and transmission.

We investigate the optical response of a gold nanorod array coupled with a semicontinuous nanoparticle film. We find that, as the gold nanoparticle film is adjusted to the percolating regime, the nanorod-film hybrids are tuned into plasmonic Fano resonance, characterized by the coherent coupling of discrete plasmonic modes of the nanorod array with the continuum band of the percolating film. Consequently, optical transmission of the percolating film is substantially enhanced.

Plasmon-mediated radiative energy transfer across a silver nanowire array via resonant transmission and subwavelength imaging.

Efficient plasmon-mediated excitation energy transfer between the CdSe/ZnS semiconductor quantum dots (QDs) across the silver nanowire array up to 560 nm in length is observed. The subwavelength imaging and spectral response of the silver nanowire arrays with near-field point-source excitations are revealed by theoretical simulations. Our studies demonstrate three advantages of the nanosystem: efficient exciton-plasmon conversion at the input side of the array through near-field strong coupling, directional waveguidance and resonant transmission via half-wave plasmon modes of the nanowire array, and subwavelength imaging at the output side of the array.

Modified effective dielectric function for metallic granular composites with high percolation threshold.

We propose the effective dielectric function theory of metal granular composites modified with the metal particle size. The modified theory is used to explain the electrical conductivity, resonant plasmon absorption, and large nonlinear absorption of Au-TiO2 granular composite films with high-density metallic particles and a high electric percolation threshold. It is revealed that the decreasing metal particle size leads to an increasing percolation threshold and large enhancement of optical nonlinearity of the composites.