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The morphologies of the fullerene targets and the ablated fullerenes are analyzed to determine the optimal conditions of excitation of the [C.sub.60]-containing targets. The optimization of fullerene-containing plasma conditions allowed the enhanced harmonic generation in fullerene-containing plasmas using laser radiation of different wavelengths, pulse durations, and phase modulation.

Investigates optical limiting in bucksminsterfullerene solution. Reduction of the pulse width; Observation of the spatial profile of the transmitted pulse; Absorption of photons from the excited state; Role of other nonlinear processes in the limiting action.

Correlation between size, bonding of Si and O at the surface/interface of Si nanocrystals and frequency of Si phonons in Si-SiO 2 nanocomposites is established using Raman mapping and X-ray photoelectron spectroscopy. Corroboration of these results with absorption spectroscopy shows that lowering of direct transition of light electron conduction band to heavy hole valence band ∼2.8 and 2.95 eV is a result of the interplay between effect of electron confinement (increases band gap) and oxidation bonding environment at the surface/interface (decreases band gap) of a nanocrystal in Si-SiO 2 nanocomposites. These studies have generated deeper insight into the fundamental understanding of the nanocomposite, which can allow easy optical microscopy monitoring of Si-SiO 2 based device fabrication. [ABSTRACT FROM AUTHOR]

Abstract: Growth of hexagonal shaped single crystal yttria stabilized zirconia nanoparticles has been observed in the vapors emanating from solid targets vaporized using CO2 laser in CW and pulsed modes of operation. The mean size and yttrium concentration in these nanoparticles are found to be in the range of 5–40nm and ∼10.4–11.6wt% respectively, which depend on the laser power density and the gaseous environment used during the growth process. Nanoparticles synthesized with pulsed mode of laser operation were found to be smaller in size compared to those generated in the CW mode. It was also found that formation of these nanoparticles was more pronounced in helium gas environment compared to those in nitrogen and argon. X-ray and electron diffraction studies showed that in all experimental conditions the generated nanoparticles were in cubic phase. From high resolution TEM it was observed that the nanoparticles with identical orientations coalesced with each other in line with the oriented attachment theory. [Copyright &y& Elsevier]