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La tomografía de coherencia óptica (OCT) permite la medición del grosor de la capa de fibras del nervio óptico (CFNR) peripapilar. El efecto de la longitud axial ocular (LA) sobre el grosor de la CFNR puede ser relevante en la interpretación de los resultados de OCT en el diagnóstico de enfermedades del nervio óptico.

We present a nonlinear optical study using standard Z-scan technique at the picosecond regime, in a nanostructured material containing both quasi-spherical silver nanoparticles and silicon quantum dots, and comparing its response to those from similar systems, one with only silicon quantum dots, and another with only silver nanoparticles. The study was done using different wavelengths, 355 nm and 532 nm, which are localized at both sides of the surface plasmon resonance of the Ag nanoparticles, and 1064 nm, which is localized well far away of it. In general, we have observed that the larger optical nonlinear response came from the sample with silver NPs. However, the combined system showed a positive nonlinear refraction below the plasmon resonance (355 nm), changing to a negative value for wavelengths above resonance (532 nm and 1064 nm). We observed also, for the combined system and for the three wavelengths used, a saturation of the nonlinear refraction index as a function of the incident irradiance.

In this paper we report the linear and non-linear optical properties of metallic nano-clusters in -Al2O3fabricated by ion implantation (from 2 to 8×1016ions/cm2). Thereafter, the samples were annealed at temperatures from 600 to 1100 °C in oxidising, reducing atmospheres. Once spherical nano-particles were synthesized, the samples were further irradiated with Si+++with different energies and fluences to control the achieved anisotropy. As a result of the ion implantation mostly F+color centers were formed. After thermal annealing they capture an electron to form F centers or combine to form a F2+center. Also, the photoluminescence signal from Al+interstitials appears. Regarding the non-linear optical response, the spherical-like Au nano-crystals embedded in sapphire show a positive non-linear absorption at 355 nm and negative non-linear absorption at 532 nm, which shows saturation when increasing the incident irradiance. They also present positive non-linear refraction at 532 nm, which is null at 355 nm. For the anisotropic systems, a larger birefringence than natural values was measured in the visible range by ellipsometry means.