Spherical gold nanoparticles and core/shell microparticles under intense femtosecond laser excitation: relaxation dynamics of gold nanoparticles and nanostructuring of borosilicate glass using microparticles

Abstract

This paper reports surface nanostructuring of borosilicate glass covered with a water layer and the production of diameter pits using core/shell microparticles under excitation with pulses using the optical scheme of an inverted microscope with a objective. We compare the thresholds for hole formation in glass with the use of and uncoated microparticles. The threshold is for and for microparticles, which coincides with the threshold for nanostructuring by a focused femtosecond pulse without microparticles: . Femtosecond pump – probe spectroscopy has been used to study the relaxation dynamics of laser pulse energy absorbed in a Au nanoparticle and the dynamics of energy dissipation to the ambient medium. The threshold for cavitation bubble formation in water with has been determined to be , which is a factor of 30 lower than the bubble formation threshold in the case of uncoated microparticles.