Observation by photothermal microscopy of increased silica absorption in laser damage induced by gold nanoparticles

Abstract

International audienceInorder to understand laser-induced damage in glass, we subjected engineeredSiO₂ thin films containing sub-micron gold inclusions to high fluences,and observed the results using several means of analysis. Wefound decoupling in time between the emission of gold andthat of silicon with samples containing gold spheres of diameter3 nm. We have analyzed the changes in the silicaoptical absorption at 1064 nm, using photothermal deflection microscopy. Wefind, upon exceeding a sharp fluence threshold, a thousand-fold increasein absorption of the silica matrix around the inclusion. Weconclude that ions from the inclusion permeate the surrounding silica,and form a highly absorbent mixture

Investigation of laser-induced damage by nanoabsorbers at the surface of fused silica

“…8 that there is a very good agreement between experimental and theoretical results (at the set of parameters γ 8 and n 0 5 × 10 6 cm −2 ) at IR irradiation compared to UV irradiation, so the size distribution and density of nano-absorbers can be obtained according to the method. Since the additional absorbing materials generated in pulse duration may have a more significant impact on the damage of fused silica at UV irradiation, there is a little discrepancy between experimental and theoretical results at UV irradiation [27]. The density of nano-absorbers obtained by the method has a good agreement with these results [19,28].…”

Gold Nanoprobes for Theranostics

“…Therefore, GNPs including nanoparticles, nanoshells, nanorods, nanocages and nanostars have shown the ability to selectively destroy cancer cells by utilizing targeting molecules and NIR heating [74,120,130]. Finally, the optical properties of GNPs have been used to develop microscopy, namely absorption, scattering, polarization and photothermal microscopy [131–135]. Finally, the photothermal properties of nanoparticles could potentially be used as a surgical tool in parts of the body considered inaccessible using traditional surgical methods.…”

X-ray spectroscopy study of electronic structure of laser-irradiated Au nanoparticles in a silica film

“…These measurements show a thousandfold increase in absorption when a sharp fluence threshold is exceeded, which indicates that a profound transformation of the silica around inclusions has occurred. 14 In summary, all these studies revealed that the defects induce a change in the silica film, which becomes absorbent and then breaks down because it takes some part of the laser energy. However, it is not yet known if the induced change concerns the atomic or electronic structure of the film.…”