MeV Si ion irradiation effects on the optical absorption properties of metallic nanoparticles embedded in silica

Anisotropic Second- and Third-Order Nonlinear Optical Response from Anisotropy-Controlled Metallic Nanocomposites

“…The Si irradiation was performed under an angle off normal of θ = (0.0° or 80.0°± 0.5°) for both, Ag and Au. As it has shown before in previous works (Oliver et al, 2006;Rodríguez-Iglesias et al, 2008), this irradiation deforms the formed NPs, transforming them in prolate spheroids all oriented along the direction of irradiation. The Si irradiation was also performed using the IFUNAM's 3MV Tandem accelerator NEC 9SDH-2 Pelletron facility.…”

“…From here, the dependence of these nonlinearities on the incident wavelength and irradiance has been observed, allowing also the observation of sign switching of the nonlinear absorption and refraction (Fernández-Hernández et al, 2011). On the other hand, the shape-anisotropy of the ion-deformed metallic NPs embedded in a dielectric matrix (Oliver et al, 2006;Rodríguez-Iglesias et al, 2008;Silva-Pereyra et al, 2010) induces also an anisotropic third-order nonlinear optical response, as we have shown for different temporal regimes, in the case of Ag and Au (Fernández-Hernández et al, 2011;Rangel-Rojo et al, 2009;Reyes-Esqueda et al, 2009;Rodríguez-Iglesias et al, 2009). For the anisotropic nanocomposites the analysis is now more complex: there are two LSPRs, one associated to the major axis of the elongated NP, and another one associated to its minor axis.…”

“…On doing so, the possibility of conferring anisotropic symmetries to metallic nanocomposites (Oliver et al, 2006;Rodríguez-Iglesias et al, 2008;Silva-Pereyra et al, 2010) revealed also the anisotropy of their linear and nonlinear optical responses (Fernández-Hernández et al, 2011;Rangel-Rojo et al, 2009Rodríguez-Iglesias et al, 2009). In particular, the anisotropic nonlinear optical response, for given wavelength and incident polarization, reveals a complex contribution from all the different, nonzero, linearly independent third-order susceptibility tensor's components Rodríguez-Iglesias et al, 2009).…”

Determination of the local gold contact morphology on a photoactive polymer film using nanobeam GISAXS

“…Typically such GISAXS experiments utilize an X-ray beam with a mean diameter on the order of 500 lm, which is provided by a synchrotron radiation facility [37][38][39][40][41][42][43][44][45][46]. Due to the shallow incident angle this beam is extended by projection onto the sample surface.…”

Elongated Gold Nanoparticles Obtained by Ion Implantation in Silica: Characterization and T-Matrix Simulations

“…14 Nonspherical nanoparticles are a good example of how one can control the optical behavior by tuning the surface plasmon resonance (SPR) associated with the presence of NPs. 9,[15][16][17][18] Illustrative of these geometries are nanoellipsoids, which exhibit three plasmon resonances corresponding to the oscillation of electrons along the three axes of the nanoparticle. By changing the length of the axes it is possible to systematically tune the frequency of the SPR.…”