  Chirality in nonlinear-optical response of planar G-shaped nanostructures; ; et al in Optics Express (2012), 20(8), 8518 Chirality effects in optical second harmonic generation (SHG) are studied in periodic planar arrays of gold G-shaped nanostructures. We show that G-shaped structures of different handedness demonstrate ... [more ▼] Chirality effects in optical second harmonic generation (SHG) are studied in periodic planar arrays of gold G-shaped nanostructures. We show that G-shaped structures of different handedness demonstrate different SHG efficiency for the left and right circular polarizations, as well as the opposite directions of the SHG polarization plane rotation. The observed effects are interpreted as the appearance of chirality in the SHG response which allows clear distinguishing of two enantiomers. [less ▲] Detailed reference viewed: 11 (1 ULg)Volumetric Method of Moments (MoM) and Conceptual Multi-level Building Blocks for nano topologies; ; et al in IEEE Photonics Journal (2012), 4(1), 267-282 Based on the relationship between charge dimensionality and singular field behavior, it is proven that in a volumetric description of a volume current carrying topology, half rooftops of different binary ... [more ▼] Based on the relationship between charge dimensionality and singular field behavior, it is proven that in a volumetric description of a volume current carrying topology, half rooftops of different binary hierarchical level are allowed without introducing numerical difficulties. This opens the possibility to use a very efficient multi-level hierarchical meshing scheme in a Volumetric Method of Moments (MoM) algorithm. The new meshing scheme is validated by numerical calculations and experiments. It paves the way towards a much more efficient use of MoM in the description of arbitrarily shaped nano-structures at IR and optical frequencies. [less ▲] Detailed reference viewed: 5 (0 ULg)Plasmon-Enhanced Sub-Wavelength Laser Ablation: Plasmonic Nanojets; ; et al in Advanced Materials (2012), 24 Plasmonic hotspots are regions on the surface of metal nanostructures where light causes very strong oscillation of the electrons. Because electron oscillations constitute an electric current and because ... [more ▼] Plasmonic hotspots are regions on the surface of metal nanostructures where light causes very strong oscillation of the electrons. Because electron oscillations constitute an electric current and because electric currents heat up the material the same way an electric stove heats up in the kitchen, the plasmonic hotspots are extremely hot. So hot that they can melt the gold in a spot much smaller than the wavelength of light. We were successfully able to demonstrate that this tiny little pool of molten gold can give rise to the smallest nanojets ever observed. [less ▲] Detailed reference viewed: 8 (1 ULg)Robustness of the scanning second harmonic generation microscopy technique for characterization of hotspot patterns in plasmonic nanomaterials; ; et al in Proceedings of SPIE (2012), 8424 Scanning second harmonic generation (SHG) microscopy is becoming an important tool for characterizing nanopatterned metal surfaces and mapping plasmonic local field enhancements. Here we study G-shaped ... [more ▼] Scanning second harmonic generation (SHG) microscopy is becoming an important tool for characterizing nanopatterned metal surfaces and mapping plasmonic local field enhancements. Here we study G-shaped and mirror-G-shaped gold nanostructures and test the robustness of the experimental results versus the direction of scanning, the numerical aperture of the objective, the magnification, and the size of the laser spot on the sample. We find that none of these parameters has a significant influence on the experimental results. [less ▲] Detailed reference viewed: 21 (0 ULg)Second harmonic hotspots at the edges of the unit cells in G-shaped gold nanostructures; ; et al in Proceedings of SPIE (2012), 8424 We report our latest results on second harmonic generation (SHG) microscopy from arrays of G-shaped chiral gold nanostructures. The nanostructures are arranged in unit cells composed of four Gs, each ... [more ▼] We report our latest results on second harmonic generation (SHG) microscopy from arrays of G-shaped chiral gold nanostructures. The nanostructures are arranged in unit cells composed of four Gs, each rotated at 90° with respect to its neighbors. As it has already been demonstrated, for linearly polarized light, these unit cells yield a pattern of four SHG hotspots. However, upon increasing the pitch of the nanostructured arrays, extra hotspots can be observed at the edges of the unit cells. While the origin of these extra hotspots remains to be elucidated, their position indicates a relationship to coupling behavior between the unit cells. [less ▲] Detailed reference viewed: 9 (0 ULg) |
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