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Keywords:

  • laser photolysis;
  • precursor;
  • nanoparticle;
  • filament;
  • polymer;
  • porous glass;
  • self-organization

Abstract

Continuous wave (CW) laser (473 nm in wavelength, 10–50 mW in power) irradiation of porous glass (Vycor) and polymer (cross-linked olygourethane-methacrylate) samples impregnated with Au precursor (H[AuCl4]·4H2O), stimulates formation of filamentary tracks from Au nanoparticles (5–90 µm in thickness and up to 5 mm in length), which are growing along a laser beam axis. Such filaments are growing both in the course of laser irradiation, and as a result of diffusive post-radiation effects. In Vycor glass sample each single filament represents itself a quasi-periodic sequence of granules composed of Au nanoparticles aggregates 10–30 µm in size, while in polymer sample the granules are non-periodic and are not so clearly pronounced. The observed effect of a low intensity CW laser formation of filaments from Au particles is rationalized by self-organization effects of several types, taking place at the formation of Au nanoparticles (with a strong plasmon resonance) and their micron-sized aggregates. The self-consistent processes of laser light filamentation and growing of filamentary tracks of Au nanoparticles aggregates are clearly revealed in such system. (© 2011 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) (© 2011 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA)