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Based on nanoscale photopolymerization triggered by the dipolar surface plasmon mode, we developed a light-emitting gold nanoparticle/Eosin Y-doped polymer hybrid nanostructure. Due to the anisotropic spatial distribution of the dipolar surface plasmon mode during photopolymerization, this nano-emitter is anisotropic in both geometry and emission. The trapped dye molecules in the hybrid nanostructure display fluorescence intensity that is dependent upon the polarization of the incident excitation light. This nano-emitter further allows the photo-selection of fluorescence configuration (i.e., molecule concentration and refractive index of active medium) by controlling the incident polarization. [ABSTRACT FROM AUTHOR]

All-optical signal processing enables modulation and transmission speeds not achievable using electronics alone. However, its practical applications are limited by the inherently weak nonlinear effects that govern photon-photon interactions in conventional materials, particularly at high switching rates. Here, we show that the recently discovered nonlocal optical behaviour of plasmonic nanorod metamaterials enables an enhanced, ultrafast, nonlinear optical response. We observe a large (80%) change of transmission through a subwavelength thick slab of metamaterial subjected to a low control light fluence of 7 mJ cm−2, with switching frequencies in the terahertz range. We show that both the response time and the nonlinearity can be engineered by appropriate design of the metamaterial nanostructure. The use of nonlocality to enhance the nonlinear optical response of metamaterials, demonstrated here in plasmonic nanorod composites, could lead to ultrafast, low-power all-optical information processing in subwavelength-scale devices. [ABSTRACT FROM AUTHOR]

Metallic nanoslit waveguides are promising candidates for ultrahigh-density optical interconnections. A variety of devices based on metallic nanoslit waveguides have already been proposed that show a great superiority over conventional photonic devices for compactness. However very few two-dimensional devices have been experimentally demonstrated with in-plane geometries due to fabrication difficulties. In this article, a feasible process is presented using traditional semiconductor fabrication technologies such as mix-and-match lithography and electroplating, which is cable of fabricating complicated 100 nm wide, 800 nm deep gold slit waveguides with multiple sharp right-angle corners. The process can be extended to volume production manufacturing with minor modifications, thus enabling the fabrication of nanoslit photonic circuits and networks. [ABSTRACT FROM AUTHOR]

Summary We report an apertureless near-field optical study on nanostructured objects formed by J-aggregates adsorbed on silver (Ag) nanoparticles. Near-field images reveal that the enhanced near-field from the dressed particle's (DP) resonantly excited plasmon oscillation is efficiently absorbed by the J-aggregates. The sensitivity of the near-field images recorded at the harmonics of the probe vibration frequency suggests that the DP is releasing part of the absorbed energy radiatively upon interaction with the probe. The role of the probe in providing this new radiative relaxation channel is further confirmed as fluorescence from the J-aggregates on the particle is detected on the particle location only. We based the interpretation of our results on the near-field optical response from a bare Ag particle excited at the plasmon resonance as well as on far-field emission and transient absorption experiments. [ABSTRACT FROM AUTHOR]

We present results of photoluminescence spectroscopy and lifetime measurements on thin film hybrid arrays of semiconductor quantum dots and metal nanoparticles embedded in a block copolymer template. The intensity of emission as well as the measured lifetime would be controlled by varying the volume fraction and location of gold nanoparticles in the matrix. We demonstrate the ability to both enhance and quench the luminescence in the hybrids as compared to the quantum dot array films while simultaneously engineering large reduction in luminescence lifetime with incorporation of gold nanoparticles. [ABSTRACT FROM AUTHOR]

We present a mechanism to control the scattering properties of individual optical nanoantennas by applying an external electric field. We find that by electrically tuning an anisotropic load medium the scattered intensity becomes voltage-dependent. We also demonstrate that the scattering diagram of the antenna can be externally adjusted. This on-demand command opens up the possibility to tune an antenna without changing its geometrical parameters. [ABSTRACT FROM AUTHOR]

We use a stochastic model to study photoinduced surface relief grating (SRG) formation due to molecular transport in azobenzene polymer films. The model is shown to reproduce the essential experimental features of SRG formation. In particular, it predicts SRG formation under both p and s polarizations, and the double peaked topographies that can occur at early times of the process. The evolving molecular positions and orientations during exposure are also followed, providing a useful mechanistic picture of SRG dynamics. [ABSTRACT FROM AUTHOR]

Apertureless scanning near-field optical microscopy is a method for obtaining subwavelength optical images of nanostructures. However, great care must be taken to avoid artifactual images. We report on one artifact related to the error signal in cantilever vibration amplitude when operating in tapping mode atomic force microscopy. The artifact is described experimentally and modeled by electromagnetic calculations based on the finite element method. We report specific steps to identify and avoid this artifact with experimental results on gold nanostructures. It is suggested that future apertureless scanning near-field optical microscopy studies verify that optical image does not correlate with error signal. [ABSTRACT FROM AUTHOR]

A correction to the article "Error Signal Artifact in Apertureless Scanning Near-Field Optical Microscopy," by L. Billot and colleagues in a 2006 issue.